I am trying to write to a 82c55 chip
Iam using an 80c32 philips micro with 28c04 eeprom .
I can write to the ports and it works ok.
when I try to write to the 82c55 it dosent work?.
I have conected a74hct138 chip to A13 A14 A15 of the address bus.
the eeprom is conected to Y0 pin 15 of the 74hct138 chip and the82c55 is conected to the Y7 pin 7 of the 138 chip.
Would this make the address F000 ?.
I only write in hex code.
The code i have tryed is listed below.
75
d0 set reg do to 00 use reg bank 0
00
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75
83 set reg to f0 high byt address
f0
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75
82 set reg to oo low byte address
11
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74 set acc to 80
80
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f0 send to address F011 (controll word 8255)
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75
82 set reg byte to 00 low byte
00
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75
83 set reg byte to F0 high byte
f0
------------------------------------
74 set acc to 55
55
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fo send to address F000 (set port to 55)
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