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Posted By

siz
on 2015-12-20
01:43:02
 Re: unused I/O location for debug purposes

Long time ago Solder created a list of the used I/O addresses including custom hardware. His site does not seem to work now (www.solder-synergy.net) but I have it mirrored (offline). The contents of the file ioarea.txt:
-------------------------------------------
Overview for the used adresses in i/o-area. Hardware-developer: This is no dictate for you. But for compatibility you should use free adresses. Mail me the adress from your hardware. I will add it to this list. solder@gmx.net

$fd00-$feff plus/4-i/o-area
$fd00-$fd0f ACIA-chip (6551/8551)
$fd00-$fd03 effective range for ACIA
$fd03-$fd0f mirrors of $fd00-$fd03
$fd10-$fd1f Userport 6529B-chip (original)
$fd10 effective adress for 6529B (original)
$fd10-$fd1f mirrors of $fd10 (original)
$fd10-$fd1f Userport-area (plus/4 with expansion)
$fd10 6529B-chip from userport
$fd11-$fd12 Centronics-printerport
$fd13-$fd14 Low-/high-switching for OS96
$fd15 Register for CSORY-RAM-expansion
$fd16 Register for Hannes-RAM-expansion
$fd17 Register for EPROM-/sRAM-expansion
$fd18-$fd1f free (best for internal expansion)
$fd20-$fd2f used by different hardware, decoded by PLA (pin 18)
$fd30-$fd3f 6529B for keyboard
$fd30 effective adress for this 6529B
$fd31-$fd3f mirrors of $fd30
$fd40-$fd5f SID-card, area for SID-chip
$fd40-$fd5d SID-chip
$fd5e DAC on digiblaster add-on
$fd5f ADC on digiblaster add-on
$fd60-$fd7f Area for expansion-userport
$fd60-$fd63 ACIA on card 1
$fd64-$fd67 ACIA on card 2
$fd68-$fd6b ACIA on card 3
$fd6c-$fd6f ACIA on card 4
$fd70-$fd73 6529B-emulation on card 1
$fd70 effective adress for 6529B-emulation
$fd71-$fd73 mirrors of $fd70
$fd74-$fd77 6529B-emulation on card 2
$fd74 effective adress for 6529B-emulation
$fd75-$fd77 mirrors of $fd74
$fd78-$fd7b 6529B-emulation on card 3
$fd78 effective adress for 6529B-emulation
$fd79-$fd7b mirrors of $fd78
$fd7c-$fd7f 6529B-emulation on card 4
$fd7c effective adress for 6529B-emulation
$fd7d-$fd7f mirrors of $fd7c
$fd80-$fd8f Joyport on SID-card
$fd80 effective adress for joyport
$fd81-$fd8f mirrors of $fd80
$fd90-$fdcf free
$fdd0-$fddf Area for ROM-banking
$fde0-$fde1 MIDI-interface
$fde2-$fdef free
$fdf0-$fdfd free
$fdfe Register on EPROM-card
$fdff Register on sRAM-card
$fe00-$fe7f free (best usage for a RAM-drive...)
$fe80-$fe9f SID-card, mirror from $fd40... for hungarian-compatibility
$fe80-$fe9d SID-chip
$fe9e DAC on digiblaster add-on
$fe9f ADC on digiblaster add-on
$fea0-$febf free (?)
$fec0-$fecf Floppy 1551, device 9
$fed0-$feef free (?)
$fef0-$feff Floppy 1551, device 8

note: please don't use mirror-adresses in your programs. Perhaps a mirror-
adress is decoded better later (like $fd10-$fd1f). Your programs will not
work then.



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