SCN2681AC1N24 Philips Semiconductors, SCN2681AC1N24 Datasheet
SCN2681AC1N24
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SCN2681 Dual asynchronous receiver/transmitter (DUART) Product specification Supersedes data of 1995 May 01 IC19 Data Handbook Philips Semiconductors INTEGRATED CIRCUITS 1998 Sep 04 ...
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... Programmable baud rate for each receiver and transmitter selectable from: – 22 fixed rates 115.2k baud ORDERING INFORMATION Commercial DESCRIPTION DESCRIPTION V = +5V +5 Plastic DIP 1 24-Pin SCN2681AC1N24 2 28-Pin SCN2681AC1N28 2 40-Pin SCN2681AC1N40 44-Pin Not available NOTES: 1. 400mil-wide Dual In-Line Package 2. 600mil-wide Dual In-Line Package 1998 Sep 04 16-bit programmable Counter/Timer – ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PIN CONFIGURATIONS IP3 2 39 IP4 IP5 IP1 4 37 IP6 IP2 CEN IP0 7 34 RESET WRN RDN 9 32 X1/CLK RXDB 10 31 RXDA DIP TXDB 11 30 TXDA OP1 12 29 OP0 OP3 13 28 OP2 OP5 14 27 OP4 OP7 ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PIN DESCRIPTION APPLICABLE SYMBOL TYPE SYMBOL TYPE 40/ D0– I/O CEN WRN RDN A0– RESET INTRN X1/CLK RxDA RxDB TxDA TxDB OP0 OP1 OP2 X O OP3 X O OP4 X O OP5 X O OP6 X O OP7 X O IP0 ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PIN DESCRIPTION (Continued) APPLICABLE SYMBOL SYMBOL TYPE TYPE 40/ IP5 X I IP6 GND ABSOLUTE MAXIMUM RATINGS SYMBOL T Operating ambient temperature range A T Storage temperature range STG All voltages with respect to ground NOTES: 1. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other condition above those indicated in the operation section of this specification is not implied ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) AC CHARACTERISTICS 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, WRN Low AS t A0-A3 hold time from RDN, WRN Low AH t CEN setup time to RDN, WRN Low ...
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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 X2 CSRA ...
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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 currently active interrupting conditions. Outputs OP3-OP7 can be programmed to provide discrete interrupt outputs for the transmitter, receivers, and counter/timer ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) generate an interrupt request at OP6 or OP7 and INTRN. When a character is loaded into the Transmit Holding Register (THR), the above conditions are negated. Data is transferred from the holding register to transmit shift register when it is idle or has completed transmission of the previous character ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) the FIFO pointers and result in the reading of previously read data. A receiver reset will re-align the pointers. Multidrop Mode The DUART is equipped with a wake up mode for multidrop applications. This mode is selected by programming bits MR1A[4:3] or MR1B[4:3] to ‘11’ for Channels A and B, respectively. In this mode of operation, a ‘ ...
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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 error conditions must be cleared by using the error reset command (command 4x receiver reset. BIT 7 BIT 6 ...
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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 Yes 1 = Yes BIT 7 BIT 6 INPUT DELTA PORT ISR BREAK B CHANGE Yes 1 = Yes BIT 7 BIT 6 IN ...
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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. MR2A[7:6] – Channel A Mode Select Each channel of the DUART can operate in one of four modes. ...
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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 via CRB. After reading or writing MR1B, the pointer will point to MR2B. ...
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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 break begins when transmission of the character is com- pleted character is in the THR, the start of the break will be delayed until that character, or any other loaded subse- quently are transmitted ...
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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 output which is the comple- ment of TxRDYB. When in this mode OP7 acts as an Open- Col- lector output ...
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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 issues a Channel B ‘reset break change interrupt’ command. ...
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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 57.6K 115.2K NOTE: Duty cycle of 16x clock is 50% 1% ...
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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 1998 Sep 04 t RES Figure 3. Reset Timing RWD NOT VALID FLOAT VALID t RWD VALID Figure 4. Bus 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 is referenced from themidpoint of the switching signal, V point 0.5V above V ...
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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( Timing shown for MR2( 1998 Sep RXS RXH SD00093 Figure 9. Receiver Timing D2 D3 ...
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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( Shown for OPCR( and MR( MASTER STATION ADD#1 TxD TRANSMITTER ...
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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 OP2 through OP7. The data source for output ports OP0 and OP1 is controlled by the MR and CR registers ...
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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 38.4K 1101 Timer 1110 I/O2 – 16X 1111 I/O2 – ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) DIP24: plastic dual in-line package; 24 leads (400 mil) 1998 Sep 04 25 Product specification SCN2681 SOT248-1 ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) DIP28: plastic dual in-line package; 28 leads (600 mil) 1998 Sep 04 26 Product specification SCN2681 SOT117-1 ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) DIP40: plastic dual in-line package; 40 leads (600 mil) 1998 Sep 04 27 Product specification SCN2681 SOT129-1 ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PLCC44: plastic leaded chip carrier; 44 leads 1998 Sep 04 28 Product specification SCN2681 SOT187-2 ...
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... Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) 1998 Sep 04 NOTES 29 Product specification SCN2681 ...
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... Philips Semiconductors for any damages resulting from such application. Right to make changes — Philips Semiconductors reserves the right to make changes, without notice, in the products, including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no ...