OVERVIEW
MC68332
3-8
USER’S MANUAL
IFETCH
CPU32
Output
—
IPIPE
CPU32
Output
—
IRQ[7:1]
SIM
Input
0
MISO
QSM
Input/Output
—
MODCLK
SIM
Input
—
MOSI
QSM
Input/Output
—
PC[6:0]
SIM
Output
(Port)
PCS[3:0]
QSM
Input/Output
—
PE[7:0]
SIM
Input/Output
(Port)
PF[7:0]
SIM
Input/Output
(Port)
PQS[7:0]
QSM
Input/Output
(Port)
QUOT
SIM
Output
—
RESET
SIM
Input/Output
0
RMC
SIM
Output
0
R/W
SIM
Output
1/0
RXD
QSM
Input
—
SCK
QSM
Input/Output
—
SIZ[1:0]
SIM
Output
—
SS
QSM
Input
0
T2CLK
TPU
Input
—
TPUCH[15:0]
TPU
Input/Output
1
TSC
SIM
Input
—
TXD
QSM
Output
—
XFC
SIM
Input
—
XTAL
SIM
Output
—
Table 3-5 MCU Signal Function
Signal Name
Mnemonic
Function
Address Bus
ADDR[23:0]
24-bit address bus
Address Strobe
AS
Indicates that a valid address is on the address bus
Autovector
AVEC
Requests an automatic vector during interrupt acknowledge
Bus Error
BERR
Indicates that a bus error has occurred
Bus Grant
BG
Indicates that the MCU has relinquished the bus
Bus Grant Acknowledge
BGACK
Indicates that an external device has assumed bus mastership
Breakpoint
BKPT
Signals a hardware breakpoint to the CPU
Bus Request
BR
Indicates that an external device requires bus mastership
System Clockout
CLKOUT
System clock output
Chip Selects
CS[10:0]
Select external devices at programmed addresses
Boot Chip Select
CSBOOT
Chip select for external boot start-up ROM
Data Bus
DATA[15:0]
16-bit data bus
Data Strobe
DS
During a read cycle, indicates when it is possible for an external
device to place data on the data bus. During a write cycle,
indicates that valid data is on the data bus.
Data and Size Acknowledge
DSACK[1:0]
Provide asynchronous data transfers and dynamic bus sizing
Development Serial In, Out,
Clock
DSI, DSO,
DSCLK
Serial I/O and clock for background debugging mode
Crystal Oscillator
EXTAL, XTAL Connections for clock synthesizer circuit reference;
a crystal or an external oscillator can be used
Table 3-4 MCU Signal Characteristics (Continued)
Signal
Name
MCU
Module
Signal
Type
Active
State
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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