Datasheet

Chapter 2 External Signal Description
MC9S08QG8 and MC9S08QG4 Data Sheet, Rev. 5
30 Freescale Semiconductor
Table 2-1. Pin Sharing Priority
Pin Number
Priority
24-pin 16-pin 8-pin Port Pin Alt 1 Alt 2 Alt 3 Alt 4
24 1 1 PTA5
1
1
Pin does not contain a clamp diode to V
DD
and should not be driven above V
DD
. The
voltage measured on the internally pulled-up RESET pin will not be pulled to V
DD
. The
internal gates connected to this pin are pulled to V
DD
.
IRQ
TCLK RESET
1 2 2 PTA4 ACMPO BKGD MS
233
V
DD
344 V
SS
45—PTB7 SCL
2
2
IIC pins can be repositioned using IICPS in SOPT2; default reset locations are on PTA2
and PTA3.
EXTAL
56—PTB6 SDA
2
XTAL
6 7 — PTB5 TPMCH1 SS
10 8 — PTB4 MISO
12 9 — PTB3 KBIP7 MOSI ADP7
13 10 — PTB2 KBIP6 SPSCK ADP6
14 11 — PTB1 KBIP5 TxD ADP5
15 12 — PTB0 KBIP4 RxD ADP4
16 13 5 PTA3 KBIP3 SCL
2
ADP3
17 14 6 PTA2 KBIP2 SDA
2
ADP2
18 15 7 PTA1 KBIP1 ADP1
3
3
If ACMP and ADC are both enabled, both will have access to the pin.
ACMP–
3
20 16 8 PTA0 KBIP0 TPMCH0 ADP0
3
ACMP+
3
Table 2-2. Pin Function Reference
Signal Function Example(s) Reference
Port Pins PTAx, PTBx Chapter 6, “Parallel Input/Output Control”
Analog comparator ACMPO, ACMP–, ACMP+ Chapter 8, “Analog Comparator (S08ACMPV2)”
Serial peripheral interface SS
, MISO, MOSI, SPSCK Chapter 15, “Serial Peripheral Interface (S08SPIV3)
Keyboard interrupts KBIPx Chapter 12, “Keyboard Interrupt (S08KBIV2)”
Timer/PWM TCLK, TPMCHx Chapter 16, “Timer/Pulse-Width Modulator (S08TPMV2)”
Inter-integrated circuit SCL, SDA Chapter 11, “Inter-Integrated Circuit (S08IICV1)”
Serial communications interface TxD, RxD Chapter 14, “Serial Communications Interface (S08SCIV3)
Oscillator/clocking EXTAL, XTAL Chapter 10, “Internal Clock Source (S08ICSV1)”
Analog-to-digital ADPx Chapter 9, “Analog-to-Digital Converter (S08ADC10V1)”
Power/core BKGD/MS, V
DD
, V
SS
Chapter 2, “External Signal Description”
Reset and interrupts RESET
, IRQ Chapter 5, “Resets, Interrupts, and General System Control”
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