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Usart control register – Rainbow Electronics AT75C220 User Manual

Page 83

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AT75C220

83

USART Control Register

Name:

US_CR

Access Type:Write-only
Reset Value:Undefined

RSTRX: Reset Receiver

0 = No effect.

1 = The receiver logic is reset.

RSTTX: Reset Transmitter

0 = No effect.

1 = The transmitter logic is reset.

RXEN: Receiver Enable

0 = No effect.

1 = The receiver is enabled if RXDIS is 0.

RXDIS: Receiver Disable

0 = No effect.

1 = The receiver is disabled.

TXEN: Transmitter Enable

0 = No effect.

1 = The transmitter is enabled if TXDIS is 0.

TXDIS: Transmitter Disable

0 = No effect.

1 = The transmitter is disabled.

RSTSTA: Reset Status Bits

0 = No effect.

1 = Resets the status bits PARE, FRAME, OVRE and RXBRK in the US_CSR.

STTBRK: Start Break

0 = No effect.

1 = If break is not being transmitted, starts transmission of a break after the characters present in US_THR and the
Transmit Shift Register have been transmitted.

STPBRK: Stop Break

0 = No effect.

1 = If a break is being transmitted, stops transmission of the break after a minimum of one character length and trans-
mits a high level during 12 bit periods.

STTTO: Start Time-out

0 = No effect.

1 = Starts waiting for a character before clocking the time-out counter.

SENDA: Send Address

0 = No effect.

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

SENDA

STTTO

STPBRK

STTBRK

RSTSTA

7

6

5

4

3

2

1

0

TXDIS

TXEN

RXDIS

RXEN

RSTTX

RSTRX