Datasheet

Chapter 13 Serial Communications Interface (S12SCIV2) Block Description
392 MC9S12C-Family / MC9S12GC-Family Freescale Semiconductor
Rev 01.24
13.3.2.5 SCI Status Register 2 (SCISR2)
Read: Anytime
Write: Anytime; writing accesses SCI status register 2; writing to any bits except TXDIR and BRK13
(SCISR2[1] & [2]) has no effect
Module Base + 0x_0005
76543210
R00000
BK13 TXDIR
RAF
W
Reset 0 0 0 00000
= Unimplemented or Reserved
Figure 13-7. SCI Status Register 2 (SCISR2)
Table 13-6. SCISR2 Field Descriptions
Field Description
2
BK13
Break Transmit Character Length — This bit determines whether the transmit break character is 10 or 11 bit
respectively 13 or 14 bits long. The detection of a framing error is not affected by this bit.
0 Break Character is 10 or 11 bit long
1 Break character is 13 or 14 bit long
1
TXDIR
Transmitter Pin Data Direction in Single-Wire Mode. — This bit determines whether the TXD pin is going to
be used as an input or output, in the Single-Wire mode of operation. This bit is only relevant in the Single-Wire
mode of operation.
0 TXD pin to be used as an input in Single-Wire mode
1 TXD pin to be used as an output in Single-Wire mode
0
RAF
Receiver Active Flag — RAF is set when the receiver detects a logic 0 during the RT1 time period of the start
bit search. RAF is cleared when the receiver detects an idle character.
0 No reception in progress
1 Reception in progress