MC68HC705 MOTOROLA [Motorola, Inc], MC68HC705 Datasheet - Page 128

• Manufacturer Part Number: MC68HC705
• Description: HCMOS Microcontroller Unit
• Manufacturer: MOTOROLA [Motorola, Inc]

Serial Communications Interface (SCI)
10.6.2 SCI Control Register 1
Technical Data
128
Address:
SCI control register 1 (SCCR1) shown in
functions:
R8 — Bit 8 (Received)
T8 — Bit 8 (Transmitted)
M — Character Length Bit
Reset:
Read:
Write:
•
•
•
When the SCI is receiving 9-bit characters, R8 is the ninth bit of the
received character. R8 receives the ninth bit at the same time that the
SCDR receives the other eight bits. Reset has no effect on the R8 bit.
When the SCI is transmitting 9-bit characters, T8 is the ninth bit of the
transmitted character. T8 is loaded into the transmit shift register at
the same time that SCDR is loaded into the transmit shift register.
Reset has no effect on the T8 bit.
This read/write bit determines whether SCI characters are eight or
nine bits long. The ninth bit can be used as an extra stop bit, as a
receiver wakeup signal, or as a mark or space parity bit. Reset has no
effect on the M bit.
1 = 9-bit SCI characters
0 = 8-bit SCI characters
Stores ninth SCI data bit received and ninth SCI data bit
transmitted
Controls SCI character length
Controls SCI wakeup method
Serial Communications Interface (SCI)
$000E
Bit 7
R8
U
Figure 10-6. SCI Control Register 1 (SCCR1)
= Unimplemented
T8
U
6
5
M
U
4
U = Unaffected
WAKE
Figure 10-6
U
3
MC68HC705C8A — Rev. 2.0
2
has these
1
MOTOROLA
Bit 0