MC9S12XD256MAL Datasheet, PDF (492/1348 Pages) Freescale Semiconductor, Inc – Freescale’s Scalable Controller Area Network

Chapter 11 Serial Communication Interface (S12SCIV5)
11.3.2.9 SCI Data Registers (SCIDRH, SCIDRL)
7
6
5
4
3
2
1
0
R
R8
0
0
0
0
0
0
T8
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 11-12. SCI Data Registers (SCIDRH)
7
6
5
4
3
2
1
0
R
R7
R6
R5
R4
R3
R2
R1
R0
W
T7
T6
T5
T4
T3
T2
T1
T0
Reset
0
0
0
0
0
0
0
0
Figure 11-13. SCI Data Registers (SCIDRL)
Read: Anytime; reading accesses SCI receive data register
Write: Anytime; writing accesses SCI transmit data register; writing to R8 has no effect
Table 11-12. SCIDRH and SCIDRL Field Descriptions
Field
SCIDRH
7
R8
SCIDRH
6
T8
SCIDRL
7:0
R[7:0]
T[7:0]
Description
Received Bit 8 — R8 is the ninth data bit received when the SCI is configured for 9-bit data format (M = 1).
Transmit Bit 8 — T8 is the ninth data bit transmitted when the SCI is configured for 9-bit data format (M = 1).
R7:R0 — Received bits seven through zero for 9-bit or 8-bit data formats
T7:T0 — Transmit bits seven through zero for 9-bit or 8-bit formats
NOTE
If the value of T8 is the same as in the previous transmission, T8 does not
have to be rewritten.The same value is transmitted until T8 is rewritten
In 8-bit data format, only SCI data register low (SCIDRL) needs to be
accessed.
When transmitting in 9-bit data format and using 8-bit write instructions,
write first to SCI data register high (SCIDRH), then SCIDRL.
MC9S12XDP512 Data Sheet, Rev. 2.21
492
Freescale Semiconductor