Digi NS7520 Enable active RTS only while transmitting, Transmit encoding, Receive data encoding

Models: NS7520

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S e r i a l C o n t r o l l e r M o d u l e

 

 

 

 

 

 

 

 

 

 

 

Bit

Access

Mnemonic

Reset

Description

 

 

 

 

 

 

 

D15

R/W

RTSTX

0

Enable active RTS only while transmitting

 

 

 

 

Note: The RTS bit in Serial Channel Control

 

 

 

 

Register A must be set if setting this

 

 

 

 

bit.

 

 

 

 

Controls the RTS indicator. Do not set this bit

 

 

 

 

if the RTSRX bit in Serial Channel Control

 

 

 

 

Register A is set.

 

 

 

 

When this bit is set, the RTS output goes

 

 

 

 

active only when the transmitter is actively

 

 

 

 

sending a transmit character. The RTSTX bit

 

 

 

 

allows external hardware to use the RTS signal

 

 

 

 

as a transmit line driver enable signal in

 

 

 

 

multi-drop applications.

 

 

 

 

 

 

D14:12

N/A

Reserved

N/A

N/A

 

 

 

 

 

 

D11:09

R/W

TENC

0

Transmit encoding

D08:06

R/W

RDEC

0

Receive data encoding

 

 

 

 

The NS7520 can be programmed to encode

 

 

 

 

and decode the serial data stream using one of

the eight methods listed here. The transmit and receive coding methods can be selected independently in the transmitter and receiver.

NRZ (000): Default. A 1 is represented by a high level for the duration of the entire bit-time; a 0 is represented by a low level during the entire bit-time.

NRZB (001). NRZB is NRZ inverted; that is, a 1 is represented by a low level during the entire bit-time and a 0 is represented by a high level during the bit-time.

NRZI-Mark (010). A 1 is represented by a transition at the beginning of the bit-time; the level that appears during the previous cell is reversed. A 0 is represented by the absence of a transition at the beginning of the bit cell.

Table 88: Serial Channel Control Register B bit definition

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Digi NS7520 manual Enable active RTS only while transmitting, Transmit encoding, Receive data encoding