External Signals
2-10
MPC823 USER’S MANUAL
MOTOROLA
EXTERNAL
SIGNALS
2
PB[18]
RTS2
L1ST2
P7
General-Purpose I/O Port B Bit 18—Bit 18 of the general-purpose I/O port B.
RTS2—The Request To Send modem signal for the serial communication controller.
L1ST2—One of eight output strobes that can be generated by the serial interface.
PB[17]
L1ST3
LCD_C
N7
General-Purpose I/O Port B Bit 17—Bit 17 of the general-purpose I/O port B.
L1ST3—One of eight output strobes that can be generated by the serial interface.
LCD_C—This is one of the LCD controller’s three extension data bits, which are
used to drive an active LCD panel. When using a 12-bit bus instead of a 9-bit bus,
the LCD_C signal is the least-significant bit of the blue 4-bit code. The blue portion
of the bus consists of LD[6:8] and LCD_C.
PB[16]
L1RQA
L1ST4
R5
General-Purpose I/O Port B Bit 16—Bit 16 of the general-purpose I/O port B.
L1RQA—The D-channel request signal for the serial interface time-division multiplex
port A.
L1ST4—One of eight output strobes that can be generated by the serial interface.
PC[15]
DREQ1
L1ST5
R16
General-Purpose I/O Port C Bit 15—Bit 15 of the general-purpose I/O port C.
DREQ1—The IDMA channel 1 request input signal.
L1ST5—One of eight output strobes that can be generated by the serial interface.
PC[14]
DREQ2
RTS2
L1ST6
T16
General-Purpose I/O Port C Bit 14—Bit 14 of the general-purpose I/O port C.
DREQ2—The IDMA channel 2 request input signal.
RTS2—The Request To Send modem signal for the serial communication controller.
L1ST6—One of eight output strobes that can be generated by the serial interface.
PC[13]
L1ST7
P13
General-Purpose I/O Port C Bit 13—Bit 13 of the general-purpose I/O port C.
L1ST7—One of eight output strobes that can be generated by the serial interface.
PC[12]
L1RQA
L1ST8
T13
General-Purpose I/O Port C Bit 12—Bit 12 of the general-purpose I/O port C.
L1RQA—The D-channel request signal for the serial interface time-division multiplex
port A.
L1ST8—One of eight output strobes that can be generated by the serial interface.
PC[11]
USBRXP
R10
General-Purpose I/O Port C Bit 11—Bit 11 of the general-purpose I/O port C.
USBRXP—Used with USBRXN, this signal is used by the USB to detect a
single-ended zero and the interconnection speed.
PC[10]
TGATE1
USBRXN
P9
General-Purpose I/O Port C Bit 10—Bit 10 of the general-purpose I/O port C.
TGATE1—The timer1/timer2 gate signal.
USBRXN—Used with USBRXP, this signal is used by the USB to detect a
single-ended zero and the interconnection speed.
PC[9]
CTS2
R8
General-Purpose I/O Port C Bit 9—Bit 9 of the general-purpose I/O port C.
CTS2—The Clear to Send Modem line for the serial communication controller.
PC[8]
CD2
TGATE1
N8
General-Purpose I/O Port C Bit 8—Bit 8 of the general-purpose I/O port C.
CD2—The Carrier Detect Modem line for the serial communication controller.
TGATE1—The timer1/timer2 gate signal.
PC[7]
USBTXP
T5
General-Purpose I/O Port C Bit 7—Bit 7 of the general-purpose I/O port C.
USBTXP—This output signal, in conjunction with USBTXN, are the transmit lines of
the USB.
PC[6]
USBTXN
N6
General-Purpose I/O Port C Bit 6—Bit 6 of the general-purpose I/O port C.
USBTXN—This output signal, in conjunction with USBTXP, are the transmit lines of
the USB.
PC[5]
L1TSYNCA
SDACK1
P6
General-Purpose I/O Port C Bit 5—Bit 5 of the general-purpose I/O port C.
L1TSYNCA—The transmit sync input for the serial interface time-division multiplex
port A.
SDACK1—The SDMA acknowledge 1output pin that is used as a peripheral
interface signal for IDMA emulation or as a CAM interface signal for Ethernet.
PC[4]
L1RSYNCA
T4
General-Purpose I/O Port C Bit 4—Bit 4 of the general-purpose I/O port C.
L1RSYNCA—The receive sync input for the serial interface time-division multiplex
port A.
Table 2-1. Signal Descriptions (Continued)
SIGNAL
PIN NUMBER
DESCRIPTION