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External Signals
2-8
MPC823 USER’S MANUAL
MOTOROLA
EXTERNAL
SIGNALS
2
IP_B6
DSDI
AT0
C7
Input Port B 6—This input signal is sensed by the MPC823 and its value and
changes are reported in the PIPR and PSCR registers of the PCMCIA interface.
Development Serial Data Input—This input signal is the data in for the debug port
interface.
Address Type 0—This bidirectional three-state signal is driven by the MPC823
when it initiates a transaction on the external bus. If high (1), the transaction is the
CPM. If low (0), the transaction initiator is the core.
IP_B7
PTR
AT3
D8
Input Port B 7—This input signal is monitored by the MPC823 and its value and
changes are reported in the PIPR and PSCR registers of the PCMCIA interface.
Program Trace—This output signal is asserted by the MPC823 to indicate that an
instruction fetch is taking place in order to allow program flow tracking.
Address Type 3—This bidirectional three-state signal is driven by the MPC823
when it initiates a transaction on the external bus. When the transaction is initiated
by the internal core, it indicates if the transfer is reserved for data transfers or a
program trace indication for instructions fetch.
MODCK1
OP2
STS
D6
Mode Clock 1—This input signal is sampled at PORESET negation to configure the
PLL/clock mode of operation.
Output Port 2—This output signal is generated by the MPC823 as a result of a write
to the PGCRB register in the PCMCIA interface.
Special Transfer Start—This output signal is driven by the MPC823 to indicate the
beginning of a transaction on the external bus or an internal transaction in show cycle
mode.
MODCK2
OP3
DSDO
B6
Mode Clock 2—This input signal is sampled at PORESET negation to configure the
PLL/clock mode of operation.
Output Port 3—This output signal is generated by the MPC823 as a result of a write
to the PGCRB register in the PCMCIA interface.
Development Serial Data Output—This output signal is the data out of the debug
port interface.
PA[15]
USBRXD
P16
General-Purpose I/O Port A Bit 15—Bit 15 of the general-purpose I/O port A.
USBRXD—The receive data input signal for the USB.
PA[14]
USBOE
R15
General-Purpose I/O Port A Bit 14—Bit 14 of the general-purpose I/O port A.
USBOE—The output enable signal for the USB transmitter.
PA[13]
RXD2
R14
General-Purpose I/O Port A Bit 13—Bit 13 of the general-purpose I/O port A.
RXD2—The receive data input signal for the serial communication controller.
PA[12]
TXD2
R13
General-Purpose I/O Port A Bit 12—Bit 12 of the general-purpose I/O port A.
TXD2—The transmit data output signal for the serial communication controller.
TXD2 has open-drain capability.
PA[9]
L1TXDA
SMRXD2
N10
General-Purpose I/O Port A Bit 11—Bit 9 of the general-purpose I/O port A.
L1TXDA—The transmit data output signal for the serial interface time-division
multiplex port A. This signal has open-drain capability.
SMRXD2—The serial management controller 2 receive data pin.
PA[8]
L1RXDA
SMTXD2
T9
General-Purpose I/O Port A Bit 8—Bit 8 of the general-purpose I/O port A.
L1RXDA—The receive data input signal for the serial interface time-division
multiplex port A.
SMTXD2—The serial management controller 2 transmit data pin.
PA[7]
CLK1
TIN1
L1RCLKA
BRGO1
T8
General-Purpose I/O Port A Bit 7—Bit 7 of the general-purpose I/O port A.
CLK1—This input signal is one of the four clock pins that can be used to clock the
serial communication controller, serial management controllers, and USB.
TIN1—The timer 1 external clock pin.
L1RCLKA—The receive clock for the serial interface time-division multiplex port A.
BRGO1—The output clock of BRG1.
PA[6]
CLK2
TOUT1
TIN3
P8
General-Purpose I/O Port A Bit 6—Bit 6 of the general-purpose I/O port A.
CLK2—This input signal is one of the four clock pins that can be used to clock the
serial communication controller, serial management controllers, and USB.
TOUT1—The timer 1 output pin.
TIN3—The timer 3 external clock pin.
Table 2-1. Signal Descriptions (Continued)
SIGNAL
PIN NUMBER
DESCRIPTION