SCN68681E1A44 NXP Semiconductors, SCN68681E1A44 Datasheet
SCN68681E1A44
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SCN68681E1A44 Summary of contents
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SCN68681 Dual asynchronous receiver/transmitter (DUART) Product data Supersedes data of 1998 Sep 04 INTEGRATED CIRCUITS 2004 Mar 02 ...
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... Detects break which originates in the middle of a character On-chip crystal oscillator Single +5 V power supply Commercial and industrial temperature ranges available DIP and PLCC packages COMMERCIAL INDUSTRIAL + – +85 C amb amb SCN68681C1N40 SCN68681E1N40 SCN68681C1A44 SCN68681E1A44 2 Product data SCN68681 DWG # SOT129-1 SOT187-2 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PIN CONFIGURATIONS A1 1 IP3 IP1 IP0 7 R/WN 8 DTACKN 9 RxDB 10 DIP TxDB 11 OP1 12 OP3 13 OP5 14 OP7 15 D1 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) BLOCK DIAGRAM 8 D0–D7 BUS BUFFER OPERATION CONTROL R/WN DTACKN ADDRESS DECODE CSN 4 A1–A4 R/W CONTROL RESETN INTERRUPT CONTROL INTRN IMR ISR IACKN IVR TIMING BAUD RATE GENERATOR CLOCK SELECTORS COUNTER/ TIMER X1/CLK ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PIN DESCRIPTION SYMBOL TYPE D0-D7 I/O Data Bus: Bidirectional 3-State data bus used to transfer commands, data and status between the DUART and the CPU the least significant bit. CSN I Chip ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) DC ELECTRICAL CHARACTERISTICS SYMBOL SYMBOL PARAMETER PARAMETER V Input LOW voltage IL V Input HIGH voltage (except X1/CLK Input HIGH voltage (except X1/CLK Input HIGH voltage (X1/CLK Output ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) AC CHARACTERISTICS T = – + amb SYMBOL SYMBOL Reset Timing (See Figure 3) t RESETN pulse width RES Bus Timing (See Figures A1-A4 set-up time ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) BLOCK DIAGRAM The SCN68681 DUART consists of the following eight major sections: data bus buffer, operation control, interrupt control, timing, communications Channels A and B, input port and output port. Refer to the Block ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) of the Output Port Register (OPR). OPR[ results in OP[n] = LOW and vice versa. Bits of the OPR can be individually set and reset. A bit is set by performing a ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) The receiver can control the deactivation of RTS. If programmed to operate in this mode, the RTSN output will be negated when a valid start bit was received and the FIFO is full. When ...
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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 MR1B RxRDY 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 IP3 IP2 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) MR1A[1:0] – Channel A Bits Per Character Select This field selects the number of data bits per character to be transmitted and received. The character length does not include the start, parity, and stop ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART external 1X clock is used for the transmitter, MR2A[ selects one stop bit and MR2A[ selects two stop bits to be transmitted. MR1B – Channel B Mode Register ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) CRA[1] – Disable Channel A Receiver This command terminates operation of the receiver immediately – a character being received will be lost. The command has no effect on the receiver status bits or any ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) OPCR[3:2] – OP3 Output Select This bit programs the OP3 output to provide one of the following: 00: The complement of OPR[3]. 01: The counter/timer output, in which case OP3 acts as an open- ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) IPCR[3:0] – IP3, IP2, IP1, IP0 Current State These bits provide the current state of the respective inputs. The information is unlatched and reflects the state of the input pins at the time the ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) In the counter mode, the C/T counts down the number of pulses loaded into CTUR and CTLR by the CPU. Counting begins upon receipt of a start counter command. Upon reaching terminal count 0000 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) RESETN t RES Figure 3. Reset Timing X1/CLK A1–A4 RWN CSN D0–D7 DTACKN X1/CLK A1–A4 RWN CSN D0–D7 DTACKN NOTE: DACKN requires two rising edges of X1 clock after CEN is low. 2004 Mar ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) X1/CLK INTRN IACKN D0–D7 DTACKN CSN IP0–IP5 CSN OP0–OP7 RxC (1X INPUT) RxD 2004 Mar 02 t CSC CSD t DAL t t DCR DAH t DAT Figure 6. Interrupt Cycle ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) t CLK t CTC X1/CLK CTCLK RxC TxC t CLK t CTC When using an external clock it is preferred to drive X2 and leave X1 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) RxC (1X INPUT) RxD TxD D1 TRANSMITTER ENABLED TxRDY (SR2) CSN (WRITE CTSN (IP0) 2 RTSN (OP0) OPR( NOTES: 1. Timing shown for MR2( Timing shown ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) MASTER STATION ADD#1 TxD TRANSMITTER ENABLED TxRDY (SR2) CSN (WRITE) MR1(4+ ADD#1 MR1( MR1( PERIPHERAL STATION BIT 9 0 ADD#1 1 RxD RECEIVER ENABLED RxRDY (SR0) CSN ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) while in the enabled state and underrun condition, is immediately disabled after a single character is loaded to the transmit holding register, that character will not be sent. In general, when it is desired ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) DIP40: plastic dual in-line package; 40 leads (600 mil) 2004 Mar 02 25 Product data SCN68681 SOT129-1 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) PLCC44: plastic leaded chip carrier; 44 leads 2004 Mar 02 26 Product data SCN68681 SOT187-2 ...
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Philips Semiconductors Dual asynchronous receiver/transmitter (DUART) REVISION HISTORY Rev Date Description _3 20040302 Product data (9397 750 12996). Supersedes data of 1998 Sep 04 (9397 750 04364). Modifications: Remove all references to 40-pin cerdip package (product discontinued). _2 19980904 Product ...
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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 ...