I/O Registers
11.8.3 SCI Control Register 3
SCI control register 3:
•
•
Stores the ninth SCI data bit received and the ninth SCI data bit to be transmitted
Enables these interrupts:
–
–
–
Receiver overrun interrupts
Noise error interrupts
Framing error interrupts
•
Parity error interrupts
Address:
$0015
Bit 7
R8
6
T8
U
5
DMARE
0
4
DMATE
0
3
2
NEIE
0
1
FEIE
0
Bit 0
PEIE
0
Read:
Write:
Reset:
ORIE
U
0
= Unimplemented
U = Unaffected
Figure 11-11. SCI Control Register 3 (SCC3)
R8 — Received Bit 8
When the SCI is receiving 9-bit characters, R8 is the read-only ninth bit (bit 8) of the received
character. R8 is received at the same time that the SCDR receives the other 8 bits.
When the SCI is receiving 8-bit characters, R8 is a copy of the eighth bit (bit 7). Reset has no effect
on the R8 bit.
T8 — Transmitted Bit 8
When the SCI is transmitting 9-bit characters, T8 is the read/write ninth bit (bit 8) of the transmitted
character. T8 is loaded into the transmit shift register at the same time that the SCDR is loaded into
the transmit shift register. Reset has no effect on the T8 bit.
DMARE — DMA Receive Enable Bit
CAUTION
The DMA module is not included on this MCU. Writing a logic 1 to DMARE
or DMATE may adversely affect MCU performance.
1 = DMA not enabled to service SCI receiver DMA service requests generated by the SCRF bit (SCI
receiver CPU interrupt requests enabled)
0 = DMA not enabled to service SCI receiver DMA service requests generated by the SCRF bit (SCI
receiver CPU interrupt requests enabled)
DMATE — DMA Transfer Enable Bit
CAUTION
The DMA module is not included on this MCU. Writing a logic 1 to DMARE
or DMATE may adversely affect MCU performance.
1 = SCTE DMA service requests enabled; SCTE CPU interrupt requests disabled
0 = SCTE DMA service requests disabled; SCTE CPU interrupt requests enabled
ORIE — Receiver Overrun Interrupt Enable Bit
This read/write bit enables SCI error CPU interrupt requests generated by the receiver overrun bit, OR.
1 = SCI error CPU interrupt requests from OR bit enabled
0 = SCI error CPU interrupt requests from OR bit disabled
MC68HC908AP Family Data Sheet, Rev. 4
Freescale Semiconductor
173
FREESCALE [ Freescale ]
