Rabbit Rabbit 4000, User Manual

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160 Rabbit 4000 Microprocessor User’s Manual
Serial Port x Extended Register (SEER) (Address = 0x00CD)
(HDLC Mode Only) (SFER) (Address = 0x00DD)
Bit(s) Value Description
7:5 000 NRZ data encoding for HDLC receiver and transmitter.
010 NRZI data encoding for HDLC receiver and transmitter.
100 Biphase-level (Manchester) data encoding for HDLC receiver and transmitter.
110 Biphase-space data encoding for HDLC receiver and transmitter.
111 Biphase-mark data encoding for HDLC receiver and transmitter.
4 0 Normal HDLC data encoding.
1
Enable RZI coding (¼ bit cell IrDA-compliant). This mode can only be used
with an internal clock and NRZ data encoding.
3 0 Idle line condition is flags.
1 Idle line condition is all ones.
2 0 Transmit flag on underrun.
1 Transmit abort on underrun.
1 0 Separate HDLC external receive and transmit clocks.
1 Combined HDLC external and transmit clock, from transmit clock pin.
0 This bit is ignored in HDLC mode.
Serial Port x Divider Low Register (SEDLR) (Address = 0x00CE)
(SFDLR) (Address = 0x00DE)
Bit(s) Value Description
7:0
Eight LSBs of the divider that generates the serial clock for this channel. This
divider is not used unless the MSB of the corresponding SxDHR is set to one.
Serial Port x Divider High Register (SEDHR) (Address = 0x00CF)
(SFDHR) (Address = 0x00DF)
Bit(s) Value Description
7 0
Disable the serial port divider and use the output of Timer A to clock the serial
port.
1
Enable the serial port divider, and use its output to clock the serial port. The
serial port divider counts modulo
n + 1 and is clocked by the peripheral clock.
6:0 Seven MSBs of the divider that generates the serial clock for this channel.