Digi NS9215 manual C e i v e B u f f e r G a P C o n t r o l r e g i s t e r

Models: NS9215

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S E R I A L C O N T RO L M O D U L E : U A RT

. . .

Receive Buffer GAP Control register. .

R e c e i v e B u f f e r G A P C o n t r o l r e g i s t e r

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Address: 9001_1010 / 9001_9010 / 9002_1010 / 9002_9010

The Receive Buffer GAP Control register configures the receive buffer gap control logic. The buffer gap timer starts when the first character in a new buffer is received.

Register

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reserved

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reserved

 

 

 

DLAB

SB

SP

EPS

PEN

STB

 

WLS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Register bit

assignment

Bits

Access

Mnemonic

Reset

Description

 

 

 

 

 

Enable transmit bit rate generation

 

D31

R/W

ENABLE

0

 

 

 

 

 

Write a 1 to enable the transmit bit rate generator.

 

 

 

 

 

 

 

D30:25

R/W

Not used

0x0

Write this field to 0.

 

 

 

 

 

 

 

D24:00

R/W

VALUE

0

Value

 

 

 

 

 

Defines the period between receiving the stop bit and

 

 

 

 

 

asserting the buffer gap timeout event.

Use this equation to compute the required divisor value: N = ((FCLK * gap_period) - 1)

FCLK = Nominal 29.4912 Mhz

gap_period = Desired buffer gap period

A reasonable setting is 64 character or 640 bit periods. GIven a data rate of 115,200 bps, the desired period is 5.55ms and the timeout value is 163,839d.

R e c e i v e C h a r a c t e r M a t c h C o n t r o l r e g i s t e r

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Addresses: 9001_1014 / 9001_1018 / 9001_901C / 9001_9020 / 9001_1024 / 9001_9014 / 9001_9018 / 9001_901C / 9001_9020 / 9001_9024 / 9002_1014 / 9002_1018 / 9002_101C / 9002_1020 / 9002_1024 / 9002_9014 / 9002_9018 / 9002_901C / 9002_9020 / 9002_9024

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Digi NS9215 manual C e i v e B u f f e r G a P C o n t r o l r e g i s t e r, Enable transmit bit rate generation