Pin:   Name:   Type:   Desc:
1      VCC     -       +5V powersupply.
2      /WR     O       Indicates that the Z80 is doing a port or memory
                       write-cycle.
3      /MREQ   O       Indicates that the Z80 is doing a memory read or
                       write-cycle.
4      /RD     O       Indicates that the Z80 is doing a port or memory
                       read-cycle.
5      /EXM1   O       Indicates memory-access on an address between 0x8000 and
                       0xBFFF.
6      A14     O       Address bit 14.
7      A13     O       Address bit 13.
8      A8      O       Address bit 8.
9      A9      O       Address bit 9.
10     A11     O       Address bit 11.
11     /EXM2   O       Indicates memory-access on an address between 0x0000 and
                       0x7FFF.
12     A10     O       Address bit 11.
13     /CE     O       Indicates that this physical port (cartridge) has been
                       selected for data-transfer.
14     D7      I/O     Data bit 7.
15     D6      I/O     Data bit 6.
16     D5      I/O     Data bit 5.
17     D4      I/O     Data bit 4.
18     D3      I/O     Data bit 3.
19     GND     -       System ground.
20     GND     -       System ground.
21     GND     -       System ground.
22     D2      I/O     Data bit 2.
23     D1      I/O     Data bit 1.
24     D0      I/O     Data bit 0.
25     A0      O       Address bit 0.
26     A1      O       Address bit 1.
27     A2      O       Address bit 2.
28     A3      O       Address bit 3.
29     A4      O       Address bit 4.
30     A5      O       Address bit 5.
31     A6      O       Address bit 6.
32     A7      O       Address bit 7.
33     A12     O       Address bit 8.
34     CONT    ?       ? If (GND? or +5V?)? is put on this pin, it tells the sms
                       that a cartridge is present? Seems to be connected to the
                       PIA?
35     VCC     -       +5V powersupply.
36     A15     O       Address bit 15.	
37     /MI     O       Together with /MREQ this output indicates that the
                       current cycle the Z80 is in is the opcode fetch.
                       Together with /IORQ this outout indicates that the
                       current cycle to Z80 is in is an interrupt acknowledge
                       cycle.
38     /IORQ   O       Indicates that the Z80 is doing a port read or
                       write-cycle.
39     /RFSH   O       This signal together with /MREQ indicates that the lowest
                       seven address-bus bits can be used as a refresh-address
                       for the systems dynamic memories.
40     /HALT   O       Indicates that the Z80 has executed a halt instrukction
                       and is awaiting either a normal interrupt with the mask
                       enabled or an non-maskable interrupt.
41     /WAIT   I       Tells the Z80 that the currently addressed memory-address
                       or port-address is not ready to transfer data.
42     /INT    I       Gives the Z80 a normal interrupt.
43     /KILLGA ?       ? Connected to the PIA.
44     /BUSRQ  I       Asks the Z80 to put control, data and addressbus in
                       tri-state.
45     /BUSAK  O       Indicates that the Z80 control, data and addressbus is in
                       tri-state.
46     /RST    I/O     Indicates if the Z80 is in reset and can be used to reset
                       both the Z80 and the rest of the system?
47     CLK     O       CPU clock pulse.
48     /KBSEL  ?       ? Connected to the VDP.
49     /CSRAM  O       Indicates memory-access on an address between 0xC000 and
                       0xFFFF.
50     /NMI-IN I       Gives the Z80 a non-maskable interrupt.