Toshiba ESTUDIO170F, Service Manual

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e-STUDIO170F Circuit Description January 2005 © TOSHIBA TEC
7 - 44
Pin function table
• Main-CPU (IC22) Signal Table
Pin No. Signal name I/O Function
1 RWX O Read/write signal (Low-active)
Requests each IC to read or write data.
2 DTACKX I Data acknowledge signal (Low-active)
The ASIC (Engine controller: IC15) indicates the end of
data transfer.
3 BGX O Bus grant signal (Low-active)
The Main-CPU (IC22) indicates the release of the bus.
4 BRX I Bus request signal (Low-active)
The ASIC (Engine controller) makes a request for bus
control.
5, 41 VCC - 3.3V
6 CPUCK I Main-CPU operation clock (16 MHz)
7, 23, 56 GND - Signal ground
8 MODE - Pull-up: 3.3V
9 HALTX O Halt signal (Low-active)
Indicates that the Main-CPU is stopped.
10 RESETX I Reset signal (Low-active)
Resets the system.
11 AVECX - Pull-up: 3.3V
12 BERRX - Pull-up: 3.3V
13-15 IPL0X-2X I Interrupt request 0-2 signals (Low-active)
The ASIC (Engine controller) makes requests for inter-
rupt processing.
16-18 FC0-2 O Main-CPU operating status 0-2 signals
Indicate the operating status of the Main-CPU to the
ASIC (Engine controller).
19 CPA[0] - Not used (Open)
20-22, 24-40,
42-44
CPA[1]-[23] O CPU address bus
45-55, 57-61 CPD[0]-[15] O CPU data bus
62 ASX O Address bus strobe signal (Low-active)
Causes the CPU address bus data to be latched.
63 UDSX O Upper data bus strobe signal (Low-active)
Causes the CPU upper data bus data to be latched.
64 LDSX O Lower data bus strobe signal (Low-active)
Causes the CPU lower data bus data to be latched.