|  About | Designed and built in Poland by Tadeusz Zawadowski, also author of Copy System +4.
This is an external card plugged into the expansion port, mounting an AY-3-8910 IC. See below about programming the chip.
The only programs (released before 2021) that feature music for this card were written by BKP, who is the owner of the Card no. 003.
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| | Programming | The card can be driven by changing the values in $FD21/22/23:
$FD23 - register number
$FD22 - write to the register
$FD21 - read from the register
| Register / bit | B7 | B6 | B5 | B4 | B3 | B2 | B1 | B0 | | R0 | Channel A Tone Period | 8-Bit Fine Tune A | | R1 | | 4-Bit Coarse Tune A | | R2 | Channel B Tone Period | 8-Bit Fine Tune B | | R3 | | 4-Bit Coarse Tune B | | R4 | Channel C Tone Period | 8-Bit Fine Tune C | | R5 | | 4-Bit Coarse Tune C | | R6 | Noise period | | 5-Bit Period control | | R7 | Enable (bit 0 = on, 1 = off) | IN/OUT | Noise | Tone | | IOB | IOA | C | B | A | C | B | A | | R8 | Channel A Envelope on/off, Volume | | Env | volume | | R9 | Channel B Envelope on/off, Volume | | Env | volume | | R10 | Channel C Envelope on/off, Volume | | Env | volume | | R11 | Envelope Period | 8-Bit Fine Tune Envelope | | R12 | | 4-Bit Coarse Tune Envelope | | R13 | Envelope Shape/Cycle | | CONT | ATT | ALT | HOLD | | R14 | I/O Port A Data Store | 8-Bit Parallel I/O on Port A | | R15 | I/O Port B Data Store | 8-Bit Parallel I/O on Port B |
A simple example, play a tone on Channel A:
LDX #$07 ;; $FE to register 7 (enable tone A)
LDA #$FE
STX $FD23
STA $FD22
LDX #$08 ;; $0F to register 8 (tone A volume to maximum)
LDA #$0F
STX $FD23
STA $FD22
LDX #$00 ;; $55 to register 0 (tone A freq to $0155)
LDA #$55
STX $FD23
STA $FD22
LDX #$01 ;; $01 to register 1
LDA #$01
STX $FD23
STA $FD22
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| | Working Card Video |
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| | Hardware (owned by members) | |
| MMS |
| 1 found. |
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