Jameco Electronics Rabbit 3000 - Manual (Page 183)

174 Rabbit 3000 Microprocessor
Table 12-15. Serial Port Control Register Ports C and D
Serial Port x Control Register (SCCR) (Address = 0xE4)
(SDCR) (Address = 0xF4)
Bit(s) Value Description
7:6
00 No operation. These bits are ignored in the async mode.
01 In clocked serial mode, start a byte receive operation.
10 In clocked serial mode, start a byte transmit operation.
11
In clocked serial mode, start a byte transmit operation and a byte receive
operation simultaneously.
5
0 Enable the receiver input.
1 Disable the receiver input.
4 x This bit is ignored.
3:2
00 8 bits per character.
01
7 bits per character. In this mode the most significant bit of a byte is ignored for
transmit, and is always zero in receive data.
10
Clocked serial mode with external clock.
Serial Port C clock is on Parallel Port PF1
Serial Port D clock is on Parallel Port PF0
11
Clocked serial mode with internal clock.
Serial Port C clock is on Parallel Port PF1
Serial Port D clock is on Parallel Port PF0
1:0
00 The serial port interrupt is disabled.
01 The serial port uses Interrupt Priority 1.
10 The serial port uses Interrupt Priority 2.
11 The serial port uses Interrupt Priority 3.