3 status register (0x04) - sr, Status register (0x04) — sr -7, Stop-bit lengths -7 – Freescale Semiconductor MPC5200B User Manual

Page 519: Status register (0x04) — sr, 3 status register (0x04)

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MPC5200B Users Guide, Rev. 1

15-8

Freescale Semiconductor

PSC Registers—MBAR + 0x2000, 0x2200, 0x2400, 0x2600, 0x2800, 0x2C00

15.2.3

Status Register (0x04)

SR

The read-only SR register shows status of the transmitter, the receiver, and the FIFO.

3

TxCTS

UART / SIR—Transmitter clear-to-send—If both TxCTS and TxRTS are enabled, TxCTS controls the
operation of the transmitter. TxCTS is not used in Codec mode.

0 =

CTS has no effect on the transmitter.

1 = Enables clear-to-send operation. The transmitter checks the state of

CTS each time it is ready

to send a character.

If

CTS is asserted, the character is sent

If it is negated, the channel TxD remains in a high state and transmission is delayed until

CTS is

asserted.

Changes in

CTS as a character is being sent do not affect its transmission.

other Modes—Reserved

4:7

SB

UART—Stop-Bit (length control)—Selects the stop bit length that is appended to the transmitted
character. Stop-bit lengths of 9/16th to 2 bits are programmable for 6-, 8-bit characters. Lengths of 1
1/16th to 2 bits are programmable for 5-bit characters. In all cases, the receiver checks only for a high
condition at the center of the first stop-bit position, that is, one bit-time after the last data bit or after
the parity bit, if parity is enabled. Therefore the receiver doesn’t support a stop bit length less than
one. Not used in Codec mode, see

Table 15-9

.

other Modes—Reserved

Table 15-9. Stop-Bit Lengths

SB

5 Bits

6–8 Bits

SB

5 Bits

6–8 Bits

SB

5–8 Bits

SB

5–8 Bits

0000

1.063

0.563

0100

1.313

0.813

1000

1.563

1100

1.813

0001

1.125

0.625

0101

1.375

0.875

1001

1.625

1101

1.875

0010

1.188

0.688

0110

1.438

0.938

1010

1.688

1110

1.938

0011

1.250

0.750

0111

1.500

1.000

1011

1.750

1111

2.000

Table 15-10. Status Register (0x04) for UART Mode

msb 0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15 lsb

R

RB

FE

PE

ORERR

Tx

EMP

Tx

RD

Y

FF

ULL

Rx

RD

Y

CDE

Error

Reserved

W

RESET:

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Table 15-11. Status Register (0x04) for SIR Mode

msb 0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15 lsb

R

RB

FE

PE

ORERR

Tx

EMP

Tx

R

D

Y

FF

U

L

L

RxRD

Y

Re

s

e

rv

e

d

Error

Reserved

W

RESET:

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Bit

Name

Description

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