Motorola MPC8260 User Manual

20-12

MOTOROLA

The UART controller reports character reception and transmission error conditions via the
BDs, the error counters, and the SCCE. Modem interface lines can be monitored by the port
C pins. Transmission errors are described in Table 20-7. 

0

Ñ

0b0

1Ð4

Fractional stop bits. For 16

´ oversampling:

1111 Last transmitted stop bit 16/16. Default value after reset.
1110 Last transmitted stop bit 15/16.
É
1000 Last transmitted stop bit 9/16.
0xxx  Invalid. Do not use.

For 32

´ oversampling:

1111 Last transmitted stop bit 32/32. Default value after reset.
1110 Last transmitted stop bit 31/32.
É
0000 Last transmitted stop bit 17/32.

For 8

´ oversampling:

1111 Last transmitted stop bit 8/8. Default value after reset.
1110 Last transmitted stop bit 7/8.
1101 Last transmitted stop bit 6/8.
1100 Last transmitted stop bit 5/8.
10xx  Invalid. Do not use.
0xxx  Invalid. Do not use.

The UART receiver can always receive fractional stop bits. The next characterÕs start bit can begin 
any time after the three middle samples have been taken.

5Ð6

Ñ

0b11

7Ð8

Ñ

0b00

9Ð14

Ñ

0b111111

15

Ñ

0b0

CTS Lost 
during 
Character 
Transmission

When CTS negates during transmission, the channel stops after Þnishing the current character. The 
CP sets TxBD[CT] and generates the TX interrupt if it is not masked. The channel resumes 
transmission after the 

RESTART

 

TRANSMIT

 command is issued and CTS is asserted. 

Note that if CTS is used, the UART also offers an asynchronous ßow control option that does not 
generate an error. See the description of PSMR[FLC] in Table 20-9.