
Signal Description
5-18
MC68302 USER’S MANUAL
MOTOROLA
triggers. TCLK2 acts as the SCC2 baud rate generator output if SCC2 is in one of the mul-
tiplexed modes.
RXD2/PA0
TXD2/PA1
RCLK2/PA2
TCLK2/PA3
CTS2/PA4
RTS2/PA5
CD2/PA6
SDS2/PA7/BRG2
NOTE: In NMSI mode, the baud rate generator outputs can also
appear on the RCLK and TCLK pins as programmed in the
SCON register.
5.15 NMSI3 PORT OR PORT A PINS OR SCP PINS
The NMSI3 port or port A pins or SCP pins are shown in Figure 5-12.
Figure 5-12. NMSI3 Port or Port A Pins or SCP Pins
These eight pins can be used either as the NMSI3 port or as the NMSI3 port (less three mo-
dem lines) and the SCP port. If the SCP is enabled (EN bit in SPMODE register is set), then
the three lines are connected to the SCP port. Otherwise, they are connected to the SCC3
port.
Each of the port A I/O pins can be configured individually to be general-purpose I/O pins or
a dedicated function in NMSI3. When they are used as the NMSI3 pins, they function exactly
Table 5-9. Baud Rate Generator Outputs
Source
NMSI
GCI
IDL
PCM
SCC1
BRG1
BRG1
BRG1
BRG1
SCC2
BRG2
TCLK2
TCLK2
TCLK2
SCC3
BRG3
TCLK3
TCLK3
TCLK3
RXD3 / PA8
TXD3 / PA9
RCLK3 / PA10
TCLK3 / PA11
CTS3 / SPRXD
RTS3 / SPTXD
CD3 / SPCLK
BRG3 / PA12
MC68302