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X68000 I/O Expansion Slot

Side A Side B
GND1 51GND
20MHz Clock 20M2 5210M 10MHz Clock
GND3 5310M 10MHz Clock
Data Bus DB004 54E Enable
Data Bus DB015 55AB00 Address Bus
Data Bus DB026 56AB01 Address Bus
Data Bus DB037 57AB02 Address Bus
Data Bus DB048 58AB03 Address Bus
Data Bus DB059 59AB04 Address Bus
Data Bus DB0610 60AB05 Address Bus
GND11 61GND
Data Bus DB0712 62AB06 Address Bus
Data Bus DB0813 63AB07 Address Bus
Data Bus DB0914 64AB08 Address Bus
Data Bus DB1015 65AB09 Address Bus
Data Bus DB1116 66AB10 Address Bus
Data Bus DB1217 67AB11 Address Bus
Data Bus DB1318 68AB12 Address Bus
Data Bus DB1419 69AB13 Address Bus
Data Bus DB1520 70AB14 Address Bus
GND21 71GND
+12V +12V22 72AB15 Address Bus
+12V +12V23 73AB16 Address Bus
CPU Function Code FC024 74AB17 Address Bus
CPU Function Code FC125 75AB18 Address Bus
CPU Function Code FC226 76AB19 Address Bus
Address Bus Confirm AS27 77AB20 Address Bus
Lower Data Strobe LDS28 78AB21 Address Bus
Upper Data Strobe UDS29 79AB22 Address Bus
Transfer Direction R/W30 80AB23 Address Bus
GND31 81GND
-12V -12V32 82HSYNC Horizontal Sync
-12V -12V33 83VSYNC Vertical Sync
Address Bus Valid VMA34 84DONE Transfer Complete (DMA)
Peripheral is addressed around 68000 family (???) EXVPA35 85DTC Transfer Complete Device (DMA)
Data Transfer Acknowledge DTACK36 86EXREQ External Request (DMA)
External Reset EXRESET37 87EXACK External Authorization (DMA)
In: CPU Halt, Out: System Stop HALT38 88EXPCL External Peripheral Control (DMA)
External Bus Error EXBERR39 89EXOWN External OWN (DMA)
External Power On EXPW.ON40 90EXNMI External NMI (DMA)
GND41 91GND
+5V Vcc242 92IRQ2-n Interrupt Request (n: slot 1 or 2)
+5V Vcc243 93IRQ4-n Interrupt Request (n: slot 1 or 2)
Memory Row/Column Switch Signal SELEN44 94IACK2-n Interrupt Enable (n: slot 1 or 2)
Memory CAS Signal (Read) CASRDEN45 95IACK4-n Interrupt Enable (n: slot 1 or 2)
Memory CAS Signal (Write Lower) CASWRL46 96BRn Bus Request
Memory CAS Signal (Write Upper) CASWRU47 97BGn Bus Grant
Main Memory Refresh Cycle INH248 98BGACK Bus Grant Acknowledge
+5V Vcc149 99Vcc1 +5V
+5V Vcc150 100Vcc1 +5V