Casio PA-2400U Service Manual And Parts List page 31

N o . Pin Name
119 CASHHB / CAS2HB
120 CASHLB / CAS2LB
121 Vss
122 Vcc
123 WE1B
124 WE0B
125 CASLHB
126 CASLLB / OEB
127 Vss
128 Vcc
129 RASB / CEB
130 MD5 / RAS2B
131 HSTBYB
132 WAITB
133 Vss
134 RTCCLK
135 Vcc(RTC)
136 XTAL2
137 EXTAL2
138 Vss(RTC)
139 Vcc
140 D31
141 D30
142 D29
143 D28
144 Vss
I n / O u t Function
O D31-D24 / D15-D8 select signal
O D23-D16 / D7-D0 select signal
GND
+3.3V source
O D15-D8 select signal
O D7-D0 select signal
O D15-D8 select signal
O D7-D0 select / memory select signal
GND
+3.3V source
O CE signal for RAM,ROM
Not used
I Not used
I Hardware wait request
GND
O RTC clock output
+3.3V source(for internal RTC)
O Oscillator terminal(for internal RTC)
I Oscillator terminal(for internal RTC)
GND(for internal RTC)
+3.3V source
I/O Data bus
I/O Data bus
I/O Data bus
I/O Data bus
GND
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To/From
BGA288,ROM Board
BGA288,ROM Board
BGA288
BGA288,LCD uint,ROM Board
BGA288,ROM Board
BGA288,ROM Board
BGA288,RAM,ROM Board
+3.3V source
BGA288
BGA288
C6
C6