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| Address Buses
|
| A0-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
|
| /CAS0
|
Active low, read on $000000-$DFFFFF region
|
| /DISK
|
0V Expansion Unit connected
|
| FREQ
|
5V = 60Hz, 0V = 50Hz
|
| /FRES
|
|
| LANG
|
5V = English, 0V = Japanese
|
| /LWR
|
Lower byte WRite
|
| /M3
|
Mark III compatibility mode
|
| Clock lines
|
| MCLK
|
Master Clock
|
| VCLK
|
68K clock
|
| ZCLK
|
Z80 clock
|
| EDCLK
|
Unknown clock
|