Sony UP-D70XR, Service Manual

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4-13
UP-D70XR
4. Port Map
a) CPU (IC101) Port map
Terminal Signal line name I/O Function
1 nRESET I Reset of CPU
2 XTAL Clock oscillator (20MHz)
3 EXTAL Clock oscillator (20MHz)
4 MD1 I Appointment of CPU operation mode
5 MD0 I Appointment of CPU operation mode
6 nNMI I Non maskable interrupt
7 nSTBY I Stand-by
8 Vss GND
9 nARB I Communication between daughter boards
10 RxD I Receiving data
11 TxD O Transmission data
12 Vss GND
13 nWAIT I Wait
14 ø System clock
15 nAS O Address strobe
16 nWR O Write signal
17 nRD O Read signal
18 nIRQ0 I DREQ break into
19 B2 O Bank switch of flash memory
20 nDACK I/O Print data acknowledgment
21 KEY_EN0 O/Hi-Z Key scan
22 KEY_EN1 O/Hi-Z Key scan
23 KEY_DAT0 I Key data
24 KEY_DAT1 I Key data
25 KEY_DAT2 I Key data
26 KEY_DAT3 I Key data
27 RS O LCD
28 R_nW O LCD
29 AVss Ground of A/D conversion
30 RBN_CD_SENS I Input of ribbon code sensor
31 BCD_SENS I Input of barcode sensor
32 OHP_SENS I Input of OHP sensor
33 HED_THERM I Thermistor value of thermal head
34 ROOM_THERM I Thermistor value of room
35 nCTS_LATCH I nCTS
36 nDREQ I/O Print data request
37 P77 I
38 AVcc Power supply of A/D conversion
39 S O Address territory switch
40 PRNT_PLS0 O Print pulse