mc68hc908qb4 Freescale Semiconductor, Inc, mc68hc908qb4 Datasheet - Page 22

• Manufacturer Part Number: mc68hc908qb4
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

General Description
1.6 Pin Function Priority
Table 1-3
22
Name
PTB4
PTB5
PTB6
PTB7
Pin
is meant to resolve the priority if multiple functions are enabled on a single pin.
PTB4 — General-purpose I/O port
RxD — ESCI receive data I/O
AD8 — A/D channel 8 input
PTB5 — General-purpose I/O port
TxD — ESCI transmit data I/O
AD9 — A/D channel 9 input
PTB6 — General-purpose I/O port
TCH2 — Timer channel 2 I/O
PTB7 — General-purpose I/O port
TCH3 — Timer channel 3 I/O
Upon reset all pins come up as input ports regardless of the priority table.
1. When a pin is to be used as an ADC pin, the I/O port function should be left as
an input and all other shared modules should be disabled. The ADC does not
override additional modules using the pin.
Pin Name
PTB0
PTB1
PTB2
PTB3
PTB4
PTB5
PTA0
PTA1
PTA4
PTA5
PTB6
PTB7
PTA2
PTA3
(1)
(1)
(1)
(1)
(1)
(1)
(1)
(1)
(1)
(1)
Table 1-3. Function Priority in Shared Pins
Table 1-2. Pin Functions (Continued)
AD0 → TCH0 → KBI0 → PTA0
AD1 → TCH1 → KBI1 → PTA1
IRQ → TCLK → KBI2 → PTA2
RST → KBI3 → PTA3
OSC2 → AD2 → KBI4 → PTA4
OSC1 → AD3 → KBI5 → PTA5
AD4 → SPSCK → PTB0
AD5 → MOSI → PTB1
AD6 → MISO → PTB2
AD7 → SS → PTB3
AD8 → RxD → PTB4
AD9 → TxD → PTB5
TCH2 → PTB6
TCH3 → PTB7
MC68HC908QB8 Data Sheet, Rev. 2
Highest-to-Lowest Priority Sequence
Description
NOTE
Freescale Semiconductor
Input/Output
Input/Output
Input/Output
Input/Output
Input/Output
Input/Output
Input/Output
Input/Output
Output
Input
Input