Pci Receiver - NCR PC4I Technical Reference

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RS-232-C SOn"IIARB CORTROL
The following asynchronous communications features
can be programmed with the 2651 integrated circuit:
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5, 6, 7, or 8-bit data characters
1, 1 1/2, or 2 stop bits
Odd, even, or no parity
Baud rates at - 50
75
110
134.5
150
300
600
1200
1800
2000
2400
3600
4800
7200
9600
19200
Line break signal generation and detection
False start bit detection
Parity overrun, and framing error detection
Internal diagnostics
The 2651 Programmable Communications Interface (PC!)
serializes parallel data provided on the system data
bus for transmission. At the same time, incoming
serial data can be converted into parallel form for
transmission to the system. PIC features are:
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Baud rate generator, generating up to 16
different baud rates
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Differentiation between communication technique
information and data on both transmitter and
receiver (TxD and RxD) lines
Allows handshaking and status information
exchange between microprocessor and connected
device
PCI Receiver
Condition for receiving data is that the CD/ input
line is low and that the RxEN bit in the Command
Register is set. In asynchronous mode, the receiver
waits for a high to low transition on RxD. One and a
half bit lengths after this transition, RxD is
sampled again. If it is now high the receiver reverts
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