MC68HC916X1
MC68HC916X1TS/D
MOTOROLA
11
2.5 MCU Signal Function
Table 6 MCU Signal Function
Signal Name
Address Bus
ADC Analog Input
Address Strobe
Bus Grant
Bus Grant Acknowledge
Bus Error
Breakpoint
Bus Request
System Clockout
Emulation Mode
Chip-Selects
Mnemonic
ADDR[19:0]
AN[5:0]
AS
BG
BGACK
BERR
BKPT
BR
CLKOUT
CSE, CSM
Function
20-bit address bus used by CPU16
Inputs to ADC multiplexer
Indicates that a valid address is on the address bus
Indicates that the MCU has relinquished the bus
Indicates that an external device has assumed bus mastership
Indicates that a bus error has occurred
Signals a hardware breakpoint to the CPU
Indicates that an external device requires bus mastership
System clock output
CSE selects external emulation devices at internally-mapped ad-
dresses. It is used to emulate I/O ports. CSM has no function on the
MC68HC916X1. It is driven high if the SCIM is configured for emu-
lation mode.
Select external devices at programmed addresses
Chip-Selects
CS10, CS[6:5],
CS3, CS0
DATA[15:0]
DS
Data Bus
Data Strobe
16-bit data bus
During a read cycle, indicates that an external device should place
valid data on the data bus. During a write cycle, indicates that valid
data is on the data bus.
Asserted by external devices during asynchronous transfers to in-
dicate receipt of data and width of receiving port
DSI, DSO, DSCLK Serial I/O and clock for background debug mode
Data and Size
Acknowledge
Development Serial In,
Out, Clock
External Clock
Crystal Oscillator
DSACK1
ECLK
M6800 bus clock output
Connections for clock synthesizer circuit reference; a crystal or an
external oscillator can be used
Identify processor state and current address space
Indicates that the CPU16 has entered background mode
Indicates instruction pipeline activity
Request interrupt service from the CPU16
Serial input to SPI in master mode; serial output from SPI in slave
mode
Selects the source and type of system clock
Serial output from SPI in master mode; serial input to SPI in slave
mode
QSPI peripheral chip selects
Port A digital input or output signals
Port B digital input or output signals
Port C digital input/output port signals
Port E digital I/O port signals
Port F digital I/O port signals
Port G digital I/O signals
GPT digital I/O port signal
Port H digital I/O signal
QSM digital I/O port signal
Input to the GPT pulse accumulator
EXTAL, XTAL
Function Codes
Freeze
Instruction Pipeline
Interrupt Request
Master In Slave Out
FC[2:0]
FREEZE
IPIPE[1:0]
IRQ[7:6]
MISO
Clock Mode Select
Master Out Slave In
MODCLK
MOSI
Peripheral Chip-Selects
Port A
Port B
Port C
Port E
Port F
Port G
Port GP
Port H
Port QS
Pulse Accumulator Input
PCS[3:0]
PA[7:0]
PB[7:0]
PC[3:0]
PE1, PE[7:4]
PF0, PF[7:6]
PG[7:0]
PGP[7:0]
PH[7:0]
PQS[7:0]
PAI