8430, Z8430 Z80 Counter-Timer Circuit. +--------------+ D4 |1 +--+ 28| D3 D5 |2 27| D2 D6 |3 26| D1 D7 |4 25| D0 GND |5 24| VCC /RD |6 23| CLK0 TRG0 ZC0 TO0 |7 Z8430 22| CLK1 TRG1 ZC1 TO1 |8 CTC 21| CLK2 TRG2 ZC2 TO2 |9 20| CLK3 TRG3 /IORQ |10 19| A1 IEO |11 18| A0 /INT |12 17| /RST IEI |13 16| /CE /M1 |14 15| CLK +--------------+ [This information is part of the GIICM]