SCD128410QCE Intel, SCD128410QCE Datasheet
SCD128410QCE
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SCD128410QCE Summary of contents
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CD1284 IEEE 1284-Compatible Parallel Interface Controller with Two High-Speed Asynchronous Serial Ports Product Features Parallel Port (Peripheral-side) High-speed, bidirectional, multi-protocol parallel port: Hardware implementation of all modes of the IEEE STD (Standard) 1284 specification (including automatic negotiation) — Centronics -compatible ...
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... Contact your local Intel sales office or your distributor to obtain the latest specifications and before placing your product order. Copies of documents which have an ordering number and are referenced in this document, or other Intel literature may be obtained by calling 1-800- 548-4725 or by visiting Intel’s website at http://www.intel.com. ...
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Contents 1.0 Overview ......................................................................................................................12 2.0 Conventions ...............................................................................................................15 2.1 Abbreviations.......................................................................................................15 2.2 Acronyms ............................................................................................................15 3.0 Pin Information 3.1 Pin Diagram.........................................................................................................17 3.2 Pin List.................................................................................................................18 4.0 Register Summary 4.1 Register Summary Tables...................................................................................24 4.2 Register Usage....................................................................................................27 5.0 Functional Description 5.1 Device Architecture .............................................................................................31 5.2 CPU ...
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... Protocol Timing ................................................................................................... 83 5.15 General-Purpose I/O Port ................................................................................... 83 5.16 Parallel Port Interface.......................................................................................... 84 5.17 Hardware Configurations .................................................................................... 86 5.17.1 Interfacing to an Intel‚ Microprocessor-Based System ........................... 86 5.17.2 Interfacing to a Motorola‚ Microprocessor-Based System...................... 86 5.17.3 Interfacing to a National Semiconductor‚ Microprocessor-Based System86 6.0 Programming 6.1 Overview ............................................................................................................. 90 6.2 Initialization ...
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Hardware-Activated Service Examples ................................................102 6.6 Baud Rate Derivation ........................................................................................102 6.7 Baud Rate Tables..............................................................................................103 6.8 ASCII Code Tables............................................................................................106 6.8.1 Hexadecimal — Character ...................................................................106 6.8.2 Decimal — Character ...........................................................................107 7.0 Detailed Register Descriptions 7.1 Global Registers................................................................................................108 7.1.1 Channel Access Register .....................................................................108 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 7.5.8 Receive Timeout Period Register......................................................... 133 7.6 Special Character Registers ............................................................................. 133 7.6.1 Special Character Register 1 ............................................................... 133 7.6.2 Special Character Register 2 ............................................................... 133 7.6.3 Special Character Register 3 ............................................................... 134 ...
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Electrical Specifications 8.1 Absolute Maximum Ratings...............................................................................155 8.2 Recommended Operating Conditions ...............................................................155 8.3 AC Characteristics.............................................................................................157 8.3.1 Asynchronous Timing...........................................................................157 8.3.2 Synchronous Timing.............................................................................163 9.0 Package Dimensions 10.0 Ordering Information 11.0 Appendix A ...............................................................................................................171 11.1 Commonly Asked Questions .............................................................................171 12.0 Appendix B ...............................................................................................................172 ...
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... FIFO Data Path Functional Diagram — Receive ................................................ 78 12 FIFO Data Path Functional Diagram — Transmit ............................................... 80 13 Cable Connection................................................................................................ 85 14 External Buffer Control........................................................................................ 86 15 Intel‚ 80x86 Family Interface ............................................................................... 87 16 Motorola‚ 68020 Interface ................................................................................... 88 17 National Semiconductor‚ 32000 Interface ........................................................... 89 18 Flow Diagram of CD1284 Master Initialization Sequence................................... 92 19 Polling Flow Chart ...
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Tables 1 Pin Descriptions ..................................................................................................20 2 Global Registers..................................................................................................24 3 Virtual Registers — Serial ...................................................................................24 4 Virtual Registers — Serial and Parallel ...............................................................24 5 Channel Registers — Serial ................................................................................25 6 Channel Registers — Parallel Pipeline (Selected by Channel 0 in CAR) ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Revision History Revision Date 1.0 May 2001 10 Description Initial release. Datasheet ...
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Figure 1. Functional Block Diagram DMA CONTROL MPU Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 Compression/ Decompression 64 Bytes DATA Mover DATA PIPELINE FIFO REGISTERS AND FIFO RAM MODIFIED CD1400 CORE GENERAL- PURPOSE I/ O PORT Control Level-2 State ...
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... CPU. Specifically for data communications applications, the RISC processor employs a high- performance architecture developed by Intel. This internal CPU executes all instructions in one clock cycle, and uses a windowed architecture to ensure zero-overhead context switching for each type of internal interrupt ...
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... PC or equivalent) through the parallel printer channel. The modes include Reverse Nibble, Reverse Byte (IBM PS/2 style), ECP, and EPP (as implemented on the Intel 80386SL processor). ECP and EPP both operate at data rates as high as 2 Mbytes/sec. ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 2. CD1284 Sample System Block Diagram CONTROL PROCESSOR GP I/O: INTERNAL STATUS AND CONTROL 14 ROM RAM ADDRESS BUS DATA BUS IEEE 1284 PARALLEL CHANNEL CD1284 HIGH-SPEED SERIAL CHANNEL #1 (RS-232, INFRARED) ...
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Conventions 2.1 Abbreviations Symbol C Hz Kbyte kHz k Mbyte MHz The use of ‘tbd’ indicates values that are ‘to be determined’, ‘n/a’ designates ‘not available’, and ‘N/C’ indicates a pin that is ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Acronym high-performance complementary metal-oxide HCMOS semiconductor HDLC high-level data link control IC integrated circuit IDC instruction and data cache ISA industry standard architecture LSB least-significant bit MPU microprocessing unit MSB most-significant bit PIO ...
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Pin Information 3.1 Pin Diagram GND 1 DB[7] 2 DB[6] 3 DB[5] 4 DB[4] 5 DB[3] 6 DB[2] 7 DB[1] 8 DB[0] 9 GND DMAACK* 12 DMAREQ* 13 RI3* 14 RI2* 15 TXD3 16 RXD3 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Pin Compati- Names bility A_128 SLCTIN* 4 HstBsy AUTOFD* HstClk STROBE* nInit INIT* AkDaR PError q PerBsy BUSY PerClk ACK* nDatAv FAULT* XFlag SELECT 3.2 Pin List The following conventions are used in ...
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Pin Name Type OUTEN I CLK I CLK/2 O DB[15:0] I/O A[6:0] I R/W* I CS* I DS* I BYTESWAP I DTACK* AR DMAREQ* O DMAACK* I SVCREQR* OD SVCACKR* I SVCREQT* OD SVCACKT* I SVCREQP* OD SVCACKP* I SVCREQM* ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Pin Name Type RXD3 I TXD2 O RXD2 I RTS2* O RTS3* O DTR2* O DTR3* O CTS2* I CTS3* I DSR2* I DSR3* I CD2* I CD3* I RI2* I RI3* I ...
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Table 1. Pin Descriptions (Sheet Symbol Pin No. Type DS BYTESWAP 82 I DTACK DMAREQ DMAACK SVCREQR SVCACKR SVCREQT SVCACKT SVCREQP* ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 1. Pin Descriptions (Sheet Symbol Pin No. Type DPASS PD[7:0] 41–48 I/O GP[7:0] 53–60 I/O A_1284 31 I nInit 34 I HstBsy 32 I HstClk 33 I ...
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Table 1. Pin Descriptions (Sheet Symbol Pin No. Type DSR[3,2]* 23 CD[3,2] 24 RI[3,2] 14 Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 Description DATA SET READY: These are active-low inputs ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 4.0 Register Summary 4.1 Register Summary Tables Table 2. Global Registers Name Hex Bit 7 Bit 6 CAR 68 Poll Poll GFRCR 4F GPDIR 71 Dir 7 Dir 6 GPIO 70 Data 7 ...
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Table 5. Channel Registers — Serial Name Hex Bit 7 Bit 6 1 CCR 05 Res Chan COR Chg CCSR 0B RxEN RxFloff COR1 08 Parity ParM1 COR2 09 IXM TxIBE COR3 0A SCDRNG SCD34 COR4 1E IGNCR ICRNL COR5 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 6. Channel Registers — Parallel Pipeline (Selected by Channel 0 in CAR) Name Hex Bit 7 Bit 6 DER 33 DMAwrerr DMArderr DMABUF (H) DMABUF (L) ...
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Table 7. Channel Registers — Parallel Port (Selected by Channel 0 in CAR) (Sheet Name Hex Bit 7 Bit 6 SPR 26 SSR ZDR 4.2 Register Usage Table 8 through Table ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 10. Virtual Registers — Serial and Parallel Name Reset Parallel Init EOSRR Table 11. Channel Registers — Serial Name Reset Parallel Init CCR CCSR COR1 COR2 COR3 COR4 COR5 LIVR LNC MCOR1 ...
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Table 12. Channel Registers — Parallel Pipeline (Selected by Channel 0 in CAR) Name Reset Parallel Init DER DMABUF (H) DMABUF (L) HRSR HTVR LIVR PACR PCRR PFCR PFEP PFFP PFHR1 PFHR2 PFQR PFSR PFTR RLCR SDTCR SDTPR Table 13. ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 13. Channel Registers — Parallel Port (Selected by Channel 0 in CAR) (Sheet Name Reset Parallel Init SCR SPR SSR ZDR NOTE: 1. Items in parentheses ( ) denote ...
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... Architecturally, the CD1284 is two devices merged into a single unit. One part is a modified, two- channel version of the Intel CD1400. The other part is a specialized parallel interface port supported by its own deep FIFO and DMA interface logic. The interrupt structure of the CD1400 has been enhanced to include the interrupt requirements of the parallel port ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 3. CD1284 Functional Block Diagram BUS INTERFACE AND DMA LOGIC INTERRUPT LOGIC Figure 4. Internal Address Generation CPU ADDRESS CAR The serial data channels are made of ‘bit engines’ that off-load the ...
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As described above, Channel separate entity comprised of its own FIFO and DMA data interface, as well as a high-speed state machine that handles all of the modes defined in the IEEE STD 1284 specification. Channel 0 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 5.2.2 Write Cycles Write cycle timing and strobe activity is nearly identical to read cycles except that the R/W* signal must be held low. Write data, strobes, and address inputs must meet setup ...
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Odd-byte transfers in the reverse direction are handled on an interrupt basis. When the number of bytes in the FIFO is odd, all bytes, except the last, are transferred by a number of 16-bit DMA cycles (two bytes per cycle). ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller At the completion of the acknowledge procedure, the CD1284 must be taken out of the acknowledge context by informing it that the procedure is complete. This restores the original internal state before the ...
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However, software can easily change this by clearing the DMAen bit (PFCR[6]) at the start of the interrupt service routine and resetting it at the end. • If SVCREQP* and DMAREQ* are logically OR’ed together, the service routine must start ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 5. Control Signal Generation CPU ADDRESS ADDRESS DECODE LOGIC CPU I/O CONTROL Table 14. Request-Type Bit Assignments Bit 2 Bit 1 Bit ...
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Another use for these bits is channel encoding. This is applicable in a single-CD1284 design and any design not using daisy-chaining (requiring a unique address range for each device). This applies where the value in the LIVR as a vector ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller One reason a design might make use of this method is that limited board space is available for the additional hardware address decoding required to generate the four SVCACK* and DGRANT* control signals. ...
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Summary of Serial Poll-Mode Service Requests The major steps involved in a Poll-mode service-request/service-acknowledge sequence are: 1. The CPU scans the SVRR periodically, checking the three least-significant bits. If any of them are true (‘1’), a service request is ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 6. CD1284 Daisy-Chain Connections ADDRESS DECODE LOGIC Before a serial request for service of a particular type is posted, the MPU checks the current state of the request output for that type. ...
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The CD1284 has a fairness override, the Unfair bit (PACR[0]). If this bit is set, the Fair Share function of the device is defeated and the MPU posts requests for service regardless of the state of the external service-request signal. ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller • NegCh for negotiation changes • SigCh for signal changes on the port status inputs (Manual mode only) • EPPAW for EPP protocol address writes • DirCh for direction changes on the parallel ...
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Figure 7. Interrupt Generation Logic KEY Current mode { } = Interface extensibility request value (see IEEE1284 Spec. for more details) (register name[x bit #, that is PCIER[1] = PCIER, bit 1 TERMINATION FAILED NEG ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 7. Interrupt Generation Logic (Continued) A1284 signal nInit signal transition from low- transition from to-high, and low-to-high, and A1284(ODR[3 nInit(ODR[2 A1284 signal nInit signal transition from transition from ...
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Figure 7. Interrupt Generation Logic (Continued) DMAwrerr DMArderr (DER[6]) (DER[7]) (DMAACK* w/o (DMAACK* w/o DMAREQ*) DMAREQ*) HR1wrerr HR1rderr (DER[3]) (DER[2]) (write to non- (Read from empty HR1) empty HR1)) DataErr Timeout OneChar (PFSR[0]) (PFSR[5]) (PFSR[1]) PPort Pipeline (PIR[6]) (PIR[5]) Datasheet ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller A direction change (DirCh) interrupt occurs when the remote master has reversed the interface from ECP forward to ECP reverse or ECP reverse to ECP forward. The IDReq interrupt is generated when the ...
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The I/O cycle that activates the SVCACKP* input also removes the active SVCREQP* output. The request output is inactive until after the CPU terminates the acknowledge routine by writing to the EOSRR. As with the serial channels, this is a ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Channel service needs, such as an empty transmit FIFO, are indicated to the CPU by one of three service-request indicators: one for all receivers, one for all transmitters, and one for all modem ...
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Following a valid start bit, the bit engine begins receiving data bits. At the end of the programmed number of bits, following bits are checked for parity (if enabled) and a valid stop bit. A valid stop bit is defined ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Type 2 If there is no data in the FIFO when the timer expires and the NNDT service request is enabled in the SRER, a receive exception service request is posted with status ...
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Figure 8. FIFO Timer Processing BACKGROUND SCANNING DETECTS NEW CHARACTER ARRIVED PUT CHARACTER IN FIFO RELOAD TIMER RESUME BACKGROUND SCANNING LOOP Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 FROM OTHER BACKGROUND PROCESSING N TIMER = ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 5.5.4 Transmitter Operation Each of the two serial channels on the CD1284 are capable of transmitting characters with a number of programmable characteristics such as length, parity, and baud rate. The channels operate ...
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The transmitter is capable of performing several special functions such as break generation, inter- character delays, and automatic flow control. These functions are discussed in 5.7, and Section 5.8. As with the receiver, the transmitter has a timer associated with ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller As previously discussed, the send special character command is preemptive to data currently in the transmit FIFO. The XOFF character is transmitted immediately after the current character and the character in the Transmitter ...
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If enabled in SCD12 and a character matching the contents of SCHR2 is received (the XOFF character), the CD1284 checks that automatic transmit in-band flow control is enabled in COR2[6]. If this function is enabled, the CD1284 stops transmission after ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 17. COR Control Bits Bit Name Register SCD12 COR3 FCT COR3 TxIBE COR2 IXM COR2 5.6.3 Out-of-Band Flow Control Flow control can also be accomplished through the modem handshake signal pairs RTS/CTS ...
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... CD1284 control. In fact, the defined DTR function enables the modem to go on- and off-line, depending on the state of the pin. If automatic flow Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 Table 18 shows the Intel recommended signal hook-up for Out-of-Band Flow CD1284 Pins Control Signal remote to ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller control is used, then DTR* goes inactive when the receive FIFO reaches the programmed threshold, causing the modem to drop the connection (carrier) to the remote, — this is not the correct use ...
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Generating Service Requests with Modem Pins The CD1284 can generate service requests when any one of the input pins changes state. Either or both edges can be detected by setting bits in MCOR1 and MCOR2. For each pin, the ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 000 Do nothing – function not enabled 001 Received NL changed to CR 010 Received CR changed to NL 011 Received CR change to NL; NL changed to CR 100 Received CR discarded ...
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Non-UNIX Receive Special Character Processing In addition to UNIX special-character processing, the CD1284 provides other special character recognition capabilities. The CD1284 has four registers that define special characters, SCHR1– SCHR4. SCHR1 and SCHR2, are used in flow-control activities and ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 9. CD1284 Receive Character Processing CHARACTER RECEIVED PARITY, FRAMING, OVERRUN ERROR ? N BREAK ? N ISTRIP ENABLED ? N SCHR12 ENABLED ? Y LNEXT FLAG SET ? N LNEXT MODE ENABLED ...
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Figure 9. CD1284 Receive Character Processing (Continued) A XOFF Y CHARACTER CHARACTER ? N SET FLOW XON Y CLEAR FLOW CHARACTER ? N IMPLIED Y CLEAR FLOW XON MODE ? N Y SCHR34 CHARACTER ENABLED ? N Y SCR CHARACTER ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 9. CD1284 Receive Character Processing (Continued) C CR/NL Y CHAR = PROCESSING ENABLED ? N PARITY PARITY Y ERROR ERROR FLAG HANDLING = ‘100’ PUT FF,00, ...
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Transmit Special Character Processing The CD1284 also provides some special character handling on the transmit side – embedded transmit commands and direct commands to transmit predefined special characters. page 70 illustrates the process of special character handling. 5.8.1 Line ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller • If there is no more data in the FIFO following the send break command, the break continues indefinitely until terminated by a stop break command. • If there is an insert delay ...
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Transmitter Holding register. This preempts any characters in the transmit FIFO. If there are characters in the transmit FIFO, transmission resumes after the special ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 10. CD1284 Transmit Character Processing READY FOR NEXT CHARACTER DELAY REPEAT CHAR MODE ACTIVE EMBEDDED N COMMAND IN PROGRESS RESET EMBEDDED COMMAND IN PROGRESS TIME = ‘0’ ...
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Figure 10. CD1284 Transmit Character Processing (Continued) A ILLEGAL CONDITION: SEND THIS AS A CHAR N Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 B Y CHAR STOP BREAK = X’ SEND ‘00’ CHAR AS CHAR = ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 10. CD1284 Transmit Character Processing (Continued) 5.9 Baud Rate Generation The CD1284 provides a separate baud rate generator both directions of each channel. Each receive and transmit baud rate generator can be ...
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The system clock is the external clock driving the CLK input of the CD1284. Three example baud rate tables are provided at the end of deriving the baud rate clock selection and divisor is also provided in 5.10 Serial Diagnostic ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller P.O. Box 1331 Pascataway, NJ 08855-1331 USA 5.11.2 Bus Interface DMA transfers are the preferred means of transferring data to/from the FIFO. However also possible to transfer data to/from the data ...
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Byte-alignment issues on transfers to/from the FIFO are avoided by having the FIFO byte-oriented with 2-byte word packing/unpacking occurring between the DMABUF register and PFHR1 and PFHR2. The order of byte transfers to/from the DMA buffer is controlled by the ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 5.11.6 Stale Data (Stale, OneChar, and Timeout Status Bits) Data transfer to the CPU can also be initiated by the ‘stale’ data timer. This timer is reloaded with the value in the SDTPR ...
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Another comparator determines if the next character coming from the DMABUF register and the character in PFHR1 are identical. Compression begins when the pipeline is full (immediately after a DMA or CPU write to the DMA buffer) and both comparators ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 20. Signal Names (Sheet Names Compatibility AkDaRq PError PerBsy BUSY PerClk ACK* nDatAv FAULT* XFlag SELECT 5.12.3 State Machine The parallel port is controlled by a large synchronous state ...
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Interrupts Interrupts are enabled in the PCIER and interrupt status can be read in the PCISR. These two registers have the same format. 5.12.6 Manual Mode Manual mode allows direct control of the five output control signals and the ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 12. FIFO Data Path Functional Diagram — Transmit (TRANSMIT) PFCR TAG BIT DB[15:8] DB[7:0] 5.12.8 Parallel Port Interface to the FIFO The DMAdir bit indicates the current direction (0 in; 1 the ...
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Negotiation Status Register After any IEEE-1284 negotiation or termination, the current protocol status can be read in the NSR. NegOK and NegFl (bits 7:6) indicate successful and failed attempts. Invalid (bit 4) indicates that the mode terminated from an invalid ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 5.13 1284 Parallel Protocol Support 5.13.1 Compatibility Mode Compatibility mode provides backward compatibility with Centronics and PC-compatible printer interfaces. When the host parallel port is in Compatibility mode (with no data transfer in ...
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The handshake is identical for both ECP and RLE modes. The control signals, HstBsy and PerBsy (in the forward and reverse directions, respectively), indicate command and address options. If HstBsy/PerBsy is low, the upper bit of the byte is examined: ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller At reset, all bits in the GPIO are cleared and the signals are programmed as inputs. Note: Interrupts are not generated on signal changes within the General-Purpose I/O port; the CPU must periodically ...
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Figure 13. Cable Connection BIDIRECTIONAL SIGNAL LINE OUTPUT SIGNAL LINE INPUT SIGNAL LINE CD1284 Caution: Transient protection is not implemented inside the CD1284 device, therefore transient voltages may cause damage. Laboratory testing has shown that this type of protection is ...
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... Microprocessor-Based System The connections between the CD1284 and an NS32000 (32GX320, 32CG16, and so on) embedded controller are also relatively simple. As with the Intel devices, cycles are controlled by the DS*, CS*, and R/W* signals synthesized from the available I/O-control signals. I/O-cycle extensions (wait states) are generated by logic connected to the DTACK* signal. All necessary controls are available to prevent multiple read/write cycles in the CD1284 FIFOs when using memory-mapped I/O ...
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... Figure 17 on page 89 Figure 15. Intel 80x86 Family Interface 80x86 SYSTEM A[23:7] ADDRESS DATA IOR* IOW* IRQ INPUTS DMA CONTROL READY Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 depicts a simplified interface example. ADDRESS DECODE LOGIC A[6:0] WAIT-STATE GENERATION LOGIC CD1284 CS* ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 16. Motorola 68020 Interface 68020 SYSTEM AS* FC[2:0] A[31:9] ADDRESS DATA DS* R/W* IPL[2:0] DMA CONTROL DSACK1* DSACK0* 88 ADDRESS DECODE LOGIC A[8:2] PRIORITY ENCODING TRANSFER CONTROL CD1284 CS* SVCACKR* SVCACKT* SVCACKM* ...
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Figure 17. National Semiconductor 32000 Interface 32000 SYSTEM D[15:0] INTERRUPT INPUTS A[31:0] IOINH* IODEC* BW0 BW1 CONF* BMT* RDY* BCLK DDIN* DMA CONTROL Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 DATA TRANSCEIVER LATCH ADDRESS DECODE AND BUS CYCLE CONTROL ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 6.0 Programming 6.1 Overview As shown in the register summary tables large array of registers. These registers control all aspects of device behavior; some affect overall chip operations, and ...
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Internal firmware uses this operation to flag completion of the reset procedure. After the reset is issued, the GFRCR is one of the first registers cleared and it is the last one set before normal runtime code execution begins. The ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 18. Flow Diagram of CD1284 Master Initialization Sequence ISSUE RESET COMMAND INIT PROCESS 92 CLEAR GFRCR N CCR = GFRCR = GFRCR N = 25* ...
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Global Function Initialization Once chip reset has been completed, the next step is to set the Global Operating mode and timer prescale. All other initialization occurs at the channel level. Set the Prescaler Period Register (PPR) The PPR sets ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller outportb(CAR, chan); outportb(RTPR, 0x14); /* set channel time-out value (20ms) */ outportb(TCOR, 0x01); /* constants for 25 MHz clock – clock option*/ outportb(TBPR, 0x51); /* outportb(RCOR, 0x01); /* constants for 25 MHz clock ...
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Once the code above locates an active request posted in the SVRR, it calls the appropriate subroutine to service the request. The service routines follow. 6.3.1.2 Serial Receive Service ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller each sequence */ case 7: status */ sequence */ } } 6.3.1.3 Serial Transmit Service /* The transmit service acknowledge routine follows very nearly the same steps that the receive service routine follows. ...
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As with the receive and transmit routines, the Interrupt register, this time the MIR, is used to force the CD1284 into the service context. */ service_mdm ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller char int vector = inportb(SVCACKR); channel = inportb(RICR) >> 2; serv_type = vector & 0x07; exception)*/ switch (serv_type) { case 3: */ chars */ each manipulate the acknowledge. */ case 7: status */ ...
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Modem Service /* The following routine services the modem change service request. Context switch is set up by activating the SVCACKM* input, reading the MIVR. The routine reads the MISR register to determine which modem signal(s) changed. Channel status ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 19. Polling Flow Chart POLL DEVICE AGAIN DMAREQ SET SERVICE DMA REQUEST DirCh CHANGE DIRECTION RETURN ID TO HOST RESET PRINTER SERVICE NEGOTIATION 6.5.1 Software-Activated Service Examples (Poll) The scanning loop for ...
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The routine below shows one way of implementing the poll-mode service activation using the first method. service_par char save_pir = inportb(PIR); value */ save_car = inportb(CAR); outportb(CAR, save_pir); */ livr_val = inportb(LIVR) & 0x07; switch (livr_val) { case ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller } outportb(PFCR, inportb(PFCR & 0xEF);/* clear IntEn (first step of ‘toggle’ operation */ outportb(PFCR, inportb(PFCR | 0x10);/* set IntEn (second step of ‘toggle’ operation */ outportb(CAR, save_car); return(0); } 6.5.2 Hardware-Activated Service Examples ...
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Baud Rate Tables Table 22 through Table 26 to set the designated baud rate when using five standard frequency crystals. MHz frequency; Table 23 24 uses a 20-MHz frequency and shows error rates that are larger although ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 23. Baud Rate Constants — CLK = 20.2752 MHz Baud Rate 110 150 300 600 1200 2400 4800 9600 19200 38400 56000 57600 64000 76800 115200 128000 150000 Table 24. Baud Rate ...
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Table 24. Baud Rate Constants — CLK = 20.00 MHz (Sheet Baud Rate 76800 115200 128000 Table 25. Baud Rate Constants — CLK = 18.432 MHz Baud Rate 110 150 300 600 1200 1800 2400 4800 9600 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 26. Baud Rate Constants — CLK = 16 MHz (Sheet Baud Rate 4800 9600 19200 38400 56000 57600 64000 76800 115200 6.8 ASCII Code Tables 6.8.1 Hexadecimal — Character ...
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Decimal — Character 0 NUL 1 SOH DLE 17 DC1 18 24 CAN ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 7.0 Detailed Register Descriptions This section presents a complete and detailed description of each register. Registers have two formats: 1) full eight bits, where the entire content defines a single function; 2) the ...
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Secondly, a system programmer can use this register to indicate when the internal processor completes reset procedures. This is done by a power-on reset (by the RESET* input software global reset (by the reset command in the CCR). ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit 7:4 User defined. Channel X: When these bits are set to the values shown below, the channel number is defined 3 1:0 User defined. 7.1.6 Modem Interrupt ...
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Bit Rxunfair, Txunfair, and Mdunfair: These bits are used by the internal processor to implement the Fair Share service request function. If this bit is set, the CD1284 does not assert another service request of this type until 5 the ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Note: This value does not have any effect on baud rate generation. The time period generated by this register drives the receive timer and activates the ‘no new data’ and ‘receive data timeout’ ...
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Bit 2 Service Request Modem: ‘1’ indicates request pending. 1 Service Request Transmit: ‘1’ indicates request pending. 0 Service Request Receive: ‘1’ indicates request pending. 7.1.12 Transmit Interrupting Channel Register Register Name: TICR Register Description: Transmit Interrupting Channel Access: Read/Write ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Virtual Registers — Serial 7.2.1 Modem Interrupt Status Register Register Name: MISR Register Description: Modem Interrupt Status Access: Read only Bit 7 Bit 6 Bit 5 DSRch CTSch RIch The MISR provides the ...
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Parallel Interrupt Vector Register Register Name: PIVR Register Description: Parallel Interrupt Vector Access: Read only Bit 7 Bit 6 Bit The value in this register is placed on the data bus, DB[7:0], when SVCACKP* is ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller provides the character not necessary to read either of these values. If the service acknowledge is terminated without reading the exception status and data from the RDSR, the internal processor updates ...
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IT2 IT1 7.2.6 Transmit Data Register Register Name: TDR Register Description: Transmit Data Access: Write only Bit 7 Bit 6 Bit 5 The transmit data register is the port for the host to write to ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Virtual Registers — All 7.2.8 End of Service Request Register Register Name: EOSRR Register Description: End of Service Request Access: Write only Bit 7 Bit 6 Bit The EOSRR ...
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Format 1 — Reset Channel Command Bit 7 Bit 6 Bit 5 Res Chan 0 0 When bit 7 is set, one of three types of reset operations are initiated, based on the value of the least- significant two ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit Description 7 This bit must always be ‘0’. 6 This bit must always be ‘1’. 5:4 These bits must always be ‘0’. These three bits are encoded as: COR3 ...
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Bit Description 5 Must be ‘1’. 4:3 Must be ‘0’. These bits are encoded as: SSPC2 2 7.3.1.4 Format 4 — Channel Control Command Bit 7 Bit 6 Bit ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit Description 7:5 Must be ‘0’. 4 Must be ‘1’. Select channel enable/disable activity: XMT EN XMT DIS 3 7.3.2 Channel Control Status Register Register ...
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Bit Transmitter Flow Off: This bit indicates that the CD1284 has been requested to stop transmission by the remote (received in-band flow control character XOFF). The bit is cleared when the CD1284 requests to 2 restart transmission (receives an XON ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit Ignore Parity: If this bit is set, the CD1284 ignores the parity on all incoming characters, thus no receive 4 exception service requests are generated if the parity is in error. If ...
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Bit Local Loopback Mode: This bit enables local loopback of the channel. This mode is generally used during system diagnostics. If this bit is set, the transmitter is internally ‘looped’ back to the receiver. The TxD pin is 4 set ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit Flow Control Transparency: This bit enables/disables the transparent response to flow control characters received by the CD1284. If set, received XON and XOFF characters are not placed in the FIFO for the ...
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Bit Carriage Return (CR) and New Line (NL) Processing: These three bits define the way that the CD1284 processes received CR and NL characters (x’0D and x’0A). The following table shows the actions performed: IGNCR ICRNL 7:5 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 7.4.5 Channel Option Register 5 Register Name: COR5 Register Description: Channel Option Register 5 Access: Read/Write Bit 7 Bit 6 Bit 5 ISTRIP LNE CMOE Bit ISTRIP: This bit enables stripping of the ...
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LNext Character Register Register Name: LNC Register Description: LNext Character Access: Read/Write Bit 7 Bit 6 Bit 5 This register defines the LNext character. If the LNext function is enabled (COR5[6]), the CD1284 examines received characters and compare them ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit DSRzd, CTSzd, RIzd and CDzd: Each of these bits controls its corresponding input pin. If the bit is set, the 7:4 function is enabled and transitions from one-to-zero (zeros detect) generate an ...
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Modem Signal Value Register 2 Register Name: MSVR2 Register Description: Modem Signal Value Register 2 Access: Read/Write Bit 7 Bit 6 Bit 5 DSR CTS RI MSVR1 and MSVR2 provide information regarding the state of the modem input pins ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller ClkSel2 7.5.7 Received Data Count Register Register Name: RDCR Register Description: Received Data Count Access: Read only Bit 7 Bit 6 Bit The RDCR indicates the ...
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Receive Timeout Period Register Register Name: RTPR Register Description: Receive Timeout Period Access: Read/Write Bit 7 Bit 6 Bit 5 The RTPR determines the time period used for the NNDT (no new data timeout) and the ‘no new data’ ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 7.6.3 Special Character Register 3 Register Name: SCHR3 Register Description: Special Character Register 3 Access: Read/Write Bit 7 Bit 6 Bit 5 7.6.4 Special Character Register 4 Register Name: SCHR4 Register Description: Special ...
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Serial Service Request Enable Register Register Name: SRER Register Description: Serial Service Request Enable Access: Read/Write Bit 7 Bit 6 Bit 5 MdmChg 0 0 This register enables the conditions that cause the CD1284, to post a service request ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 7.6.10 Transmit Clock Option Register Register Name: TCOR Register Description: Transmit Clock Option Access: Read/Write Bit 7 Bit 6 Bit The TCOR selects the clock source which drives the ...
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Bit DMA Write Error: This bit is set if the DMA control logic has written to the DMA buffer when it already 7 contains data. It indicates that an invalid DMA transfer cycle occurred (a DMAACK* without a corresponding DMAREQ*). ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller These resisters can be read through DMA acknowledge or PIO cycles, however, the DMABUF registers can only be read when the DMAREQ* signal is active. If DMAREQ* is inactive, the DMABUF registers will ...
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Bits User-defined Interrupt Vector: Host software can use these five bits for any purpose appropriate to the application. In some cases, these bits might define the rest of a complete interrupt response vector (Motorola- 7:3 type systems). In the case ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit 2 Reserved: Must be ‘0.’ AsyncDMA: AsyncDMA causes the device to synchronize the DMAACK* signal to the internal clock (rising clock edge). This capability provides an asynchronous DMA interface for systems that ...
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Bit FIFO Reset: This bit must be set together with the correct value of DMAdir to properly initialize the data pipeline and FIFO registers for data transfer or when a new data transfer direction is desired. Any data 7 remaining ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller The PFEP is cleared by a device or FIFO reset. 7.7.10 Parallel FIFO Fill Pointer Register Register Name: PFFP Register Description: Parallel FIFO Fill Pointer Access: Read/Write Bit 7 Bit 6 Bit 5 ...
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These registers are cleared by a device or FIFO reset and marked as empty in HRSR. Any tagged status is also cleared. 7.7.13 Parallel FIFO Quantity Register Register Name: PFQR Register Description: Parallel FIFO Quantity Access: Read/Write Bit 7 Bit ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit Stale: This bit is set when the stale data timer expires (see the description of SDTPR single byte remains in the data pipeline when this bit is set, a host ...
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In the transmit direction, strings of three or more identical characters are recognized and compressed. The running count of identical characters is kept in the RLCR. Once the sequence is broken by a different character or the end of the ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller The SDTPR is cleared by a device reset. 7.8 Channel Registers — Parallel Port 7.8.1 EPP Address Register Register Name: EAR Register Description: EPP Address Access: Read/Write Bit 7 Bit 6 Bit 5 ...
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It counts up until either the expected event occurs or the count matches the value in HTVR match occurs, a timeout condition exists. The HTVR need only be loaded once, typically during ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 7.8.4 Manual Data Register Register Name: MDR Register Description: Manual Data Access: Read/Write Bit 7 Bit 6 Bit 5 This read/write register can read the state of the PD[7:0] signals in any mode. ...
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Bit 7 Negotiation OK: The state of this bit indicates that the negotiation was successful. Negotiation Failed: The state of this bit indicates that the negotiation failed. The result code indicates which 6 mode was attempted Host Timeout: This bit ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Setting the bits in this register enables the CD1284 to generate an interrupt – if SigCh (PCIER[4]) is set – when the selected signal changes from low-to-high (rising edge). Bits 7:4 are reserved ...
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PCIER and PCISR provide control and status of interrupts generated by the parallel channel control state machine. They have the same bit definitions. Each bit in the PCIER enables the interrupt of the same type in the PCISR. A write ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Bit Mode Control: These three bits control the type of transfer desired and whether or not it is enabled to do so. The ManMd bit selects Manual mode, which allows the user direct ...
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Bit 7:5 These read-only bits are always ‘0’. TestMux: When this bit is set, the state of the state machine is multiplexed onto the GPIO pins for debugging purposes. 4 GPIO is not possible when this bit is set. Clear ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller slow masters that require an ACK* pulse longer than the maximum specified in the IEEE STD 1284 specification. The table below shows some examples of the necessary binary value for various system clock ...
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Electrical Specifications Note: Verify with your local sales office that you have the latest datasheet before finalizing a design. 8.1 Absolute Maximum Ratings • Supply voltage (V • Input voltages, with respect to ground-0 • Operating ...
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... As noted in the Texas Instruments ALS/AS Logic Data Book (1986 — pages 4-18 and 4-19), the V output of these families exceeds 3 low-current loading. Other manufacturers OH publish similar data. Intel recommends the use of one of these two options for the CLK input to ensure fast, clean edges. Note that RESET* can, if desired, be pulled up passively with 1-k resistor. 156 ...
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AC Characteristics 8.3.1 Asynchronous Timing Refer to the Figures 6-1 through 6-7 for the reference numbers in the following table. Table 27. Asynchronous Timing Reference Parameters (Sheet Timing Figure Number Figure t RESET* low pulse width ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 27. Asynchronous Timing Reference Parameters (Sheet Timing Figure Number The following timing numbers are for the back-to-back asynchronous DMA timing diagrams Hold time, DMAACK* active (DMA read/write) ...
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Figure 21. Clock Timing CLK Figure 22. Asynchronous Read Cycle Timing t 2 A[6: R/W* CS* DS* DB[15:0] DTACK* Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 23. Asynchronous Write Cycle Timing t 2 A[6: R/W* CS* DS* DB[15:0] DTACK* 160 ...
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Figure 24. Asynchronous Service Acknowledge Cycle Timing t 2 A[6: R/W* SVCACK* SVCREQ DS* DGRANT* DB[15:0] DTACK* DPASS* Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 25. Asynchronous DMA Read Cycle Timing CLK DMAACK* DMAREQ* DB[15:0] NOTES: NOTES: 1. The DMA handshake operates in asynchronous mode only if the AsyncDMA bit is set in PACR. 1. The DMA ...
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Figure 27. Asynchronous DMA Write Cycle Timing CLK DMAACK* DMAREQ* DB[15:0] NOTE: Figure 27 is still valid, however, Figure 28. Asynchronous DMA Write Cycle Timing (Two Back-to-Back DMA Writes) CLK DMAACK* SYNCHRONIZED DMAREQ* DMAACK* DB[15:0] NOTE: The data is sampled ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Table 28. Synchronous Timing Reference Parameters Timing Figure Number t 29 Setup time, CS* and DS rising edge Setup time, R/ rising edge ...
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Figure 29. Synchronous Read Cycle Timing CLK t 1 DS*, CS* t2 R/W* t3 A[6:0] DB[15:0] DTACK* Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 30. Synchronous Write Cycle Timing CLK t 1 DS A[6:0] DB[15:0] DTACK* 166 ...
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Figure 31. Synchronous Service Acknowledge Cycle Timing CLK t 12 SVCACK* SVCREQ* DPASS DS* DGRANT R/W* DB[15:0] DTACK* Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller Figure 32. Synchronous DMA Write Cycle Timing (Two Back-to-Back 3-Cycle DMA Writes) C CLK t 15 DMAREQ DMAACK* DB[15:0] NOTE: The data is sampled on the second rising edge of CLK ...
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... MAX NOTES: 1. Dimensions are in millimeters (inches), and controlling dimension is millimeter. 2. Before beginning any new design with this device, please contact Intel for the latest package information. Datasheet IEEE 1284-Compatible Parallel Interface Controller — CD1284 22.95 (0.904) 23.45 (0.923) 19.90 (0.783) 20 ...
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... CD1284 — IEEE 1284-Compatible Parallel Interface Controller 10.0 Ordering Information The order number for the CD1284 is: Communications, Data Contact Intel Corporation for up-to-date information on revisions. 170 SCD128410QCE Product line: Part number Internal reference number † Revision Temperature range Commercial Package type: ...
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... Device ID At this time, Intel has no more information about device ID other than that is listed on page 52 of the IEEE 1284 specification. Contact Larry Stein, Chair of the IEEE 1284.3 working group, at Far Point Communications (Fax: (805) 726-4438) for more information. Far Point Communications also sells IEEE 1284-compliant ISA add-in boards for the PC ...
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CD1284 — IEEE 1284-Compatible Parallel Interface Controller 12.0 Appendix B Figure 34. UART to RS232 and IR Port Interface Motherboard Example Schematic + AGND 7 BPV23NF PINC 6 PINA TSHA5502 + 5.2 W (2) ...
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Index A A_1284 19 AB[6:0] 19 abbreviations 15 acronyms 15 AkDaRq 19 asynchronous serial data protocol 50 B baud rate derivation 102 generation 72 tables 103 bit engines 50 BYTESWAP 19 CCLK 20 CLK 19 CLK/2 19 common ...
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H hardware-activated service examples 97 HstBsy 19 HstClk request 82 IEEE Standards Department 73 IEEE STD 1284 73 Implied XON mode 57 in-band flow control 55 initialization 90 interface 74 interrupts 36 DirCh 48 EPPAW 44 IDReq ...
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IVR 26, 29 LIVR 26, 29, 38 MDR 26, 29 NER 26, 29 NSR 26, 29 ODR 26, 29 OVR 26, 29 PACR 26, 29 PCIER 26, 29 PCISR 26, 29 PCR 26, 29 PCRR 26, 29 PFCR 26, 29 ...
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Remote Loopback mode 73 RESET* 18, 54 RLE (run-length-encoding) 75 RTS* 55 RTS2* 20 RTS3* 20 RxD 73 RXD2 20 RXD3 20 RxFloff 56 RxFlon 56 S scanning loop 94 SCHR1 55 SCHR2 55 Serial Poll mode 94 serial receive ...