Jameco Electronics 3000 ユーザーズマニュアル
User’s Manual
161
12. R
ABBIT
S
ERIAL
P
ORTS
The Rabbit 3000 has 6 on-chip serial ports designated A, B, C, D, E, and F. All the ports can per-
form asynchronous serial communications at high baud rates. Ports A-D can operate as clocked
ports. Ports A and B can be switched to alternate pins. Ports E and F support SDLC/HDLC syn-
chronous communications in addition to standard asynchronous communications. Port A has the
special capability of being used to remote boot the microprocessor via asynchronous, synchro-
nous, or IrDA (asynchronous serial).
form asynchronous serial communications at high baud rates. Ports A-D can operate as clocked
ports. Ports A and B can be switched to alternate pins. Ports E and F support SDLC/HDLC syn-
chronous communications in addition to standard asynchronous communications. Port A has the
special capability of being used to remote boot the microprocessor via asynchronous, synchro-
nous, or IrDA (asynchronous serial).
Table 12-1 lists the synchronous serial port signals.
Table 12-1. Serial Port Signals
Serial Port
Signal Name
Function
Serial Port A
TXA
Serial Transmit Out
RXA
Serial Transmit In
CLKA
Clock for clocked mode (bidirectional)
ATXA
Alternate serial transmit out
ARXA
Alternate serial receive in
Serial Port B
TXB
Serial Transmit Out
RXB
Serial Transmit In
CLKB
Clock for clocked mode (bidirectional)
ATXB
Alternate serial transmit out
ARXB
Alternate serial receive in
Serial Port C
TXC
Serial Transmit Out
RXC
Serial Transmit In
CLKC
Clock for clocked mode (bidirectional)
Serial Port D
TXD
Serial Transmit Out
RXD
Serial Transmit In
CLKD
Clock for clocked mode (bidirectional)
Serial Port E
TXE
Serial Transmit Out
RXE
Serial Transmit In
TCLKE
Optional external transmit clock
RCLKE
Optional external receive clock