Kreisen 3 8 6 X / X E - Manual (Page 153)

System Timing
System Clock Speed:
Speed CPU
High 33MHz (25MHz)
L O W 8MH.z (8MHz)
l/O
8MHz
8MHz
Clock Cycle Time:
125ns (8MHz)
40ns (25MHz)
30ns (33MHz)
I/O Address Map
Hex range Device
000-01F DMA controller 1, 8237A-5
120-03F Interrupt controller 1, 8259A, Master
040 - 05F Timer, 8254-2
060 - 06F 8042 (Keyboard)
070 - 07F Real-trme clock NMI mask
080 - 09F DMA page register, 74LS612
0A0 - 0BF Interrupt controller 2, 8237A-5
0C0 - 0DF DMA controller 2, 8237A-5
OF0 Clear math coprocessor busy
OF1 Reset math coprocessor
OF8 - OFF Math coprocessor
378 - 37F Parallel port on board
3F0 - 3F7 FDD control on board
3F8 - 3FF Serial port on board
Note: I/O address hex 000 to FFF are reserved for the system board 110
Hex 100 to 3FF are available on the I/O channel.
A-4 Specifications