ST16C452PS Exar Corporation, ST16C452PS Datasheet
ST16C452PS
Related parts for ST16C452PS
ST16C452PS Summary of contents
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... Mbps. The 452/452PS is available pin PLCC package. The 452/452PS is compatible with the 16C450. The 452 is available in two versions, the ST16C452 and the ST16C452PS. The ST16C452 provides single hardware pin to control the printer port data direction while the 452PS provides an additionally software control bit to control the printer port data direction to become compatible PS/2 operating system ...
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ST16C452/452PS Figure 1, Block Diagram D0-D7 -IOR -IOW -RESET BIDEN A0-A2 -CSA -CSB -CSP INT A,B INTP Rev. 3.20 Transmit Transmit Holding Shift Registers Register Receive Receive Holding Shift Registers Register Printer Data Ports Printer Control Logic Modem Control Clock ...
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SYMBOL DESCRIPTION Symbol Pin -ACK 68 -AutoFDXT 56 BIDEN 1 BUSY 66 CLK 4 -CSA 32 -CSB 3 -CSP 38 D0-D7 14-21 Rev. 3.20 ST16C452/452PS Signal Type I Address-0 Select Bit - Internal registers ...
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ST16C452/452PS SYMBOL DESCRIPTION Symbol Pin -ERROR 63 GND 2,7,54 27 INIT 57 INT A/B 45,60 -INTP 59 INTSEL 43 -IOR 37 Rev. 3.20 Signal Type I Error, Printer (with internal pull-up) - General purpose input or line printer error. This ...
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SYMBOL DESCRIPTION Symbol Pin -IOW 36 PD7-PD0 46- RDOUT 44 -RESET 39 N.C. 9,61 SLCT 65 -SLCTIN 58 Rev. 3.20 ST16C452/452PS Signal Type for either UART channels A/B or A0-A1 for the printer port, onto D0-D7 data bus ...
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ST16C452/452PS SYMBOL DESCRIPTION Symbol Pin -STROBE 55 N.C. 22,42 VCC 23,40,64 -CD A/B 29,8 -CTS A/B 28,13 -DSR A/B 31,5 -DTR A/B 25,11 -RI A/B 30,6 Rev. 3.20 Signal Type with a printer to select the printer with an active ...
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SYMBOL DESCRIPTION Symbol Pin -RTS A/B 24,12 RX A/B 41,62 TX A/B 26,10 Rev. 3.20 ST16C452/452PS Signal Type individual UART channels, A through B. A logic 0 on this pin(s) indicates the modem has received a ringing signal from the ...
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... The 452 is avail- able in two versions, the ST16C452 and the ST16C452PS. The ST16C452 provides single hard- ware pin to control the printer port data direction while the 452PS provides an additionally software control bit to control the printer port data direction to become compatible PS/2 operating system ...
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Table 4, INTERNAL REGISTER DECODE READ MODE General Register Set (THR/RHR, IER/ISR, MCR/MSR, LCR/LSR, SPR): Note Receive Holding Register Interrupt Status Register ...
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ST16C452/452PS The generator divides the input 16X clock by any divisor from -1. The 452/452PS divides the basic 16 external clock by 16. The basic 16X clock provides table rates to support standard and custom applications using ...
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D0-D7. The user optionally compares the received data to the initial transmitted data for verifying error free operation of the UART TX/RX circuits. In this mode, the receiver and transmitter interrupts Figure 6, INTERNAL ...
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... In the ST16C452PS, the port direction is determined as de- scribed in Table 6. When BIDEN is a logic 1 a single control bit (D5) in the control register sets the input or output mode ...
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REGISTER FUNCTIONAL DESCRIPTIONS The following table delineates the assigned bit functions for the eighteen 452/452PS internal registers. The assigned bit functions are more fully defined in the following paragraphs. Table 7, ST16C452/452PS INTERNAL REGISTERS Register BIT-7 [Default] ...
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ST16C452/452PS Register BIT-7 [Default] Note 5* Printer Port Register Set: Note 3* [ PR[00] bit-7 [ PR[00] bit-7 [ SR[4F] -Busy [ IOSEL bit-7 [ COM[E0] logic ...
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Interrupt Enable Register (IER) The Interrupt Enable Register (IER) masks the inter- rupts from receiver ready, transmitter empty, line status and modem status registers. These interrupts would normally be seen on the INT A,B output pins. IER BIT-0: This interrupt ...
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ST16C452/452PS ISR BIT-0: Logic interrupt is pending and the ISR contents may be used as a pointer to the appropriate interrupt service routine. Logic interrupt pending. (normal default condi- tion) ISR BIT 1-3: (logic ...
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LCR LCR LCR Parity selection Bit-5 Bit-4 Bit parity Odd parity Even parity Force parity odd parity Forced even parity LCR BIT-6: When enabled ...
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ST16C452/452PS LSR BIT-3: Logic framing error. (normal default condition) Logic 1 = Framing error. The receive character did not have a valid stop bit(s). LSR BIT-4: Logic break condition. (normal default condi- tion) Logic ...
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Scratchpad Register (SPR) The ST16C452/452PS provides a temporary data register to store 8 bits of user information. PRINTER PORT REGISTER DESCRIPTIONS Port Register (PR) PR BIT 0-7: Printer Data port (Bi-directional) - These pins are the eight bit data bus ...
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ST16C452/452PS a logic 1 first. Logic 0 = -AutoFDXT pin is a logic 1. (normal default condition) 1= -AutoFDXT pin is a logic 0. COM BIT-2: INIT is a bi-directional signal with an open source driver and internal pull-up so ...
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CON BIT-5: [452PS only] This bit is used in conjunction with the state of BIDEN to set the direction (input/output) of the PD7-PD0 data bus. Logic 0 + BIDEN 1 = PD7-PD0 are set for output mode (normal default condition) ...
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ST16C452/452PS AC ELECTRICAL CHARACTERISTICS T =0° - 70°C (-40° - +85°C for Industrial grade packages), Vcc=3.3 - 5.0 V ± 10% unless otherwise specified. A Symbol Parameter T ,T Clock pulse duration Oscillator/Clock frequency 3w T Address ...
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ABSOLUTE MAXIMUM RATINGS Supply range Voltage at any pin Operating temperature Storage temperature Package dissipation DC ELECTRICAL CHARACTERISTICS T =0° - 70°C (-40° - +85°C for Industrial grade packages), Vcc=2.97 - 5.5V unless otherwise specified. A Symbol Parameter V Clock ...
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ST16C452/452PS 0-D 7 Rev. 3. lid A dd ress ...
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T2w EXTERNAL CLOCK Active -IOW -RTS Change of state -DTR -CD -CTS -DSR INT -IOR -RI Rev. 3.20 ST16C452/452PS T1w T3w External clock timing T17d Change of state Change of state T18d Active T19d Active Modem input/output timing 25 EX-CK-1 ...
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ST16C452/452PS START BIT RX INT -IOR Rev. 3.20 DATA BITS (5- DATA BITS 6 DATA BITS 7 DATA BITS 16 BAUD RATE CLOCK Receive timing 26 STOP BIT D6 D7 PARITY NEXT BIT ...
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START BIT TX INT -IOW Active Rev. 3.20 ST16C452/452PS DATA BITS (5- DATA BITS 6 DATA BITS 7 DATA BITS T23d 16 BAUD RATE CLOCK Transmit timing 27 STOP BIT PARITY ...
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ST16C452/452PS -ACK T40d INTP -IOR T40s NORMAL MODE INTSEL PD0-PD7 Rev. 3.20 T39w INTERRUPT LATCHED MODE SELECT T41h VALID DATA Printer port timing 28 T42d T43d X552-PR-2 ...
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Rev. 3.20 ST16C452/452PS 29 ...
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... While the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. EXAR Corporation does not recommend the use of any of its products in life support applications where the failure of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized ...