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Pinout
Signals
Address Buses
|
A1-A23
|
M68K Address Bus
|
ZA0-ZA15
|
Z80 Address bus
|
Data Buses
|
D0-D15
|
M68K Data bus
|
ZD0-ZD7
|
Z80 Data bus
|
IO port lines
|
EM1X
|
Port 1 lines
|
EM2X
|
Port 2 lines
|
EM3X
|
Port 3 lines
|
Control lines
|
M68K related control lines
|
/BG
|
Bus Grant
|
/BGACK
|
Bus Grand Acknowledge
|
/BR
|
Bus Request
|
FC0
|
Function Code 0, 1 = Accessing user data
|
FC1
|
Function Code 1, 1 = Accessing user program
|
/HALT
|
Halt 68K execution
|
/RESET
|
Reset 68K
|
/VPA
|
Valid Peripheral Access
|
/AS
|
Address strobe
|
/DTACK
|
Data Acknowledge
|
/UDS
|
Accessing even bytes
|
/LDS
|
Accessing odd bytes
|
R/W
|
Read/Write pin, 0 = write 1 = read
|
Z80 related control lines
|
/ZM1
|
Opcode fetch strobe
|
/ZRD
|
Read strobe
|
/ZWR
|
Write strobe
|
/ZMREQ
|
Memory request
|
/ZIORQ
|
IO request
|
/ZNMI
|
Non-maskable IRQ
|
/ZBR
|
Bus request
|
/ZBAK
|
Bus Acknowledge
|
/ZRES
|
Reset Z80
|
/ZWAIT
|
Wait
|
Address decoding related control lines
|
/ASEL
|
Read or Write on $000000-$7FFFFF region
|
/CAS0
|
Read or Write on $000000-$DFFFFF region
|
/RAS0
|
Read or Write on $E00000-$FFFFFF region, act as /CE signal for the RAM chips
|
/CE0
|
Chip Enable for the cartridge, low when accessing $000000-$3FFFFF region when expension unit isn't inserted or $400000-$7FFFFF when it is.
|
/TIME
|
Read or Write on $A13000-$A130FF region
|
/LWR
|
Lower byte WRite
|
/UWR
|
Upper byte WRite
|
/NOE
|
/OE signal for the lower part of the RAM
|
/EOE
|
/OE signal for the upper part of the RAM
|
/ZREF
|
Unknown, tied to unused pin #1 of Z80 RAM
|
/ZRAM
|
/CE for the Z80 RAM
|
Configuration related control lines
|
/DISK
|
0V Expansion Unit connected
|
FREQ
|
5V = 60Hz, 0V = 50Hz
|
/FRES
|
|
LANG
|
5V = English, 0V = Japanese
|
/M3
|
Mark III compatibility mode
|
VRAM related control lines
|
/CAS1
|
Column address strobe
|
/RAS1
|
Row address strobe
|
/SE0
|
Serial data bus /OE
|
SC
|
Serial clock
|
/WE0
|
Write enable
|
/OE1
|
Output enable
|
Clock lines
|
MCLK
|
Master Clock
|
VCLK
|
68K clock
|
ZCLK
|
Z80 clock
|
EDCLK
|
Unknown clock
|