Motorola Commercial Series Service Information page 28

3-12
IC Designator
U401
Microprocessor
U402
EEPROM
U404
Flash ROM
Pin Pin Function
82 PA3_IC4_OC5_OC1
83 PA4_OC4_OC1
84 PA5_OC3_OC1
85 PA6_OC2_OC1
86 PA7_PA1_OC1
87 VSSR
88 VDDR
89 ECLK (NU)
90 EXTAL
91 XTAL
92 VDDSYN
93 XFC (NU)
94 RESET
95 LVOUT
96 IRQ
97 PD0_RXD
98 PD1_TXD
99 PD2_MISO
100 PD3_MOSI
1 Chip select
2 Serial data out
3 Write protect
4 Vss
5 Serial data in
6 Serial clock
7 Hold
8 Vcc
1 A11
2 A9
3 A8
4 A13
5 A14
6 NC
7 EN_WE
8 Vcc
9 RESET
TROUBLESHOOTING TABLES
DC Voltage Comments (Condition)
3.00
0 Squelch detect input
0 Channel activity input
0
0
GND
3.23
1.60
1.70 Clock from U451-28
1.40 Not used
0
0
3.20 From U320
0
3.20
3.23
1.9
0
3.23
3.23 From U401-3
0
3.23
GND
3.23
0
3.23
3.23
3.06
3.08
3.05
0.13
0.31
3.17
3.21 From U401-4
3.23
3.20