SCN2681AE1A44 NXP Semiconductors, SCN2681AE1A44 Datasheet
SCN2681AE1A44
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SCN2681AE1A44 Summary of contents
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SCN2681 Dual asynchronous receiver/transmitter (DUART) Product specification Supersedes data of 1998 Sep 04 INTEGRATED CIRCUITS 2004 Mar 18 ...
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... SCN2681AC1N40 DIP40 plastic dual in-line package; 40 leads (600 mil) Industrial – + amb SCN2681AE1A44 PLCC44 plastic leaded chip carrier; 44 leads SCN2681AE1N28 DIP28 plastic dual in-line package; 28 leads (600 mil) SCN2681AE1N40 DIP40 plastic dual in-line package; 40 leads (600 mil) 2004 Mar 18 16-bit programmable Counter/Timer – ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PIN CONFIGURATION IP3 2 39 IP4 IP5 IP1 4 37 IP6 IP2 CEN IP0 7 34 RESET WRN 8 33 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) Pin SYMBOL SYMBOL DIP28 DIP40 PLCC44 X1/CLK RxDA RxDB TxDA TxDB OP0 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) 1 ABSOLUTE MAXIMUM RATINGS SYMBOL T Operating ambient temperature range amb T Storage temperature range stg All voltages with respect to ground NOTES: 1. Stresses above those listed under Absolute Maximum Ratings may cause ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) AC CHARACTERISTICS T = – +85 C amb SYMBOL PARAMETER SYMBOL PARAMETER Reset Timing (Figure 3) t RESET pulse width RES 6 Bus Timing (Figure 4) t A0-A3 setup time to RDN, ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) BLOCK DIAGRAM 8 D0–D7 BUS BUFFER OPERATION CONTROL RDN WRN ADDRESS DECODE CEN 4 A0–A3 R/W CONTROL RESET INTERRUPT CONTROL INTRN IMR ISR TIMING BAUD RATE GENERATOR CLOCK SELECTORS COUNTER/ TIMER X1/CLK XTAL OSC ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) (IMR) and the Interrupt Status Register (ISR). The IMR may be programmed to select only certain conditions to cause INTRN to be asserted. The ISR can be read by the CPU to determine all ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) TRANSMITTER OPERATION The SCN2681 is conditioned to transmit data when the transmitter is enabled through the command register. The SCN2681 indicates to the CPU that it is ready to accept a character by setting ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) the FIFO and re-align the FIFO read/write pointers. This has the appearance of “clearing or flushing” the receiver FIFO. In fact, the FIFO is NEVER cleared! The data in the FIFO remains valid until ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) Table 2. Register Bit Formats BIT 7 BIT 6 RxRTS RxINT CONTROL SELECT MR1A MR1A RxRDY MR1B 1 = Yes 1 = FFULL NOTE: *In block error mode, block ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) Table 2. Register Bit Formats (Continued) BIT 7 BIT 6 BRG SET ACR SELECT MODE AND SOURCE 0 = set set 2 BIT 7 BIT 6 DELTA DELTA IPCR IP 3 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) MR2A – Channel A Mode Register 2 MR2A is accessed when the Channel A MR pointer points to MR2, which occurs after any access to MR1A. Accesses to MR2A do not change the pointer. ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) MR1B – Channel B Mode Register 1 MR1B is accessed when the Channel B MR pointer points to MR1. The pointer is set to MR1 by RESET ‘set pointer’ command applied ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) 110 Start break. Forces the TxDA output Low (spacing). If the transmitter is empty the start of the break condition will be delayed up to two bit times. If the transmitter is active the ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) OPCR – Output Port Configuration Register OPCR[7] – OP7 Output Select This bit programs the OP7 output to provide one of the following: – The complement of OPR[7]. – The Channel B transmitter interrupt ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) ISR[6] – Channel B Change In Break This bit, when set, indicates that the Channel B receiver has detected the beginning or the end of a received break reset when the CPU ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) Table 3. Bit Rate Generator Characteristics Crystal or Clock = 3.6864MHz NORMAL RATE (BAUD 110 134.5 150 200 300 600 1050 1200 1800 2000 2400 4800 7200 9600 14.4K 19.2k 28.8K 38.4k ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) TIMING DIAGRAMS RESET A0– CEN t CS RDN D0–D7 FLOAT (READ) WDN D0–D7 (WRITE) RDN IP0–IP6 WRN OP0–OP7 2004 Mar 18 t RES Figure 3. Reset Timing ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) TIMING DIAGRAMS (Continued) NOTES: 1. INTRN or OP3 – OP7 when used as interrupt outputs. 2. The test for open-drain outputs is intended to guarantee switching of the output transistor. Measurement of this response ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) TIMING DIAGRAMS (Continued) RxC (1X INPUT) RxD TxD D1 TRANSMITTER ENABLED TxRDY (SR2) WRN CTSN (IP0) 2 RTSN (OP0) OPR( NOTES: 1. Timing shown for MR2( ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) TIMING DIAGRAMS (Continued) D1 RxD RECEIVER ENABLED RxRDY (SR0) FFULL (SR1) RxRDY/ FFULL 2 (OP5) RDN STATUS DATA D1 OVERRUN (SR4) 1 RTS (OP0) OPR( NOTES: 1. Timing shown for MR1(7) = ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) Output Port Notes The output ports are controlled from three places: the OPCR register, the OPR register, and the MR registers. The OPCR register controls the source of the data for the output ports ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) Table 5. Baud Rates Extended CSR[7:4] ACR[ 0000 50 0001 110 0010 134.5 0011 200 0100 300 0101 600 0110 1,200 0111 1,050 1000 2,400 1001 4,800 1010 7,200 1011 9,600 1100 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PLCC44: plastic leaded chip carrier; 44 leads 2004 Mar 18 25 Product data SCN2681 SOT187-2 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) DIP28: plastic dual in-line package; 28 leads (600 mil) 2004 Mar 18 26 Product data SCN2681 SOT117-1 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) DIP40: plastic dual in-line package; 40 leads (600 mil) 2004 Mar 18 27 Product data SCN2681 SOT129-1 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) REVISION HISTORY Rev Date Description _3 20040318 Product data (9397 750 13043). Supersedes Product specification of 04 Sep 1998 (9397 750 04362). Modifications: Remove references to SCN2681AC1N24 and SCN2681AE1N24 Type numbers, 24-pin DIP package ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) Data sheet status Product [1] Level Data sheet status [2] [3] status I Objective data Development II Preliminary data Qualification III Product data Production [1] Please consult the most recently issued data sheet before ...