Commodore 64 - Page 54

Processor I/O Port (6510)
so ooo
IN | IN
OUT
IN OUT OUT OUT
OUT
$0001
Tape
Motor
Tape
Sense
Tape
Write
D-ROM
Switch
EF RAM
Switch
AB RAM
Switch
DDR 0
PR 1
SID (6581)
Voice 1 Voice 2
Voice 3
Voice 1
Voice 2 Voice 3
SD400 SD407
SD40E L 54272
54279 54286
SD401
SD408
SD40F
Frequency
H
54273
54280
54287
SD402
SD409
SD410
Pulse Width
L
54274
54281
54288
SD403 SD40A
SD411 0
0 0 0
H 54275
54282 54289
SD404
SD40B
SD412
NSE ,
Voice Type:
, PUL . SAW
. TRI ,
i
Key
54276
54283
54290
SD405
SD40C
SD413
Attack Time
, 2ms 7 8ms
. ii
Decay Time
6ms -.24 sec ,
54277
54284 54291
SD406
SD40D
SD414
Sustain Level
_____ i
i
_____ i
Release Time
, 6ms ,24 sec ,
54278
54285 54292
Voices (write only)
SD415
0
0 0
0
0
L
54293
SD416
Filter Frequency’
H 54294
SD417
Resonance
i Ext
Filter Voices
V3 . V2 ,
VI
54295
$D418
V3 off
Passband:
, HI , BP
. LO
l
_____
Master
, Volyme
54296
Filter & Volume (write only)
SD419
$D41 A
SD41B
SD41C
Paddle X (A /D 'l)
Paddle Y (A/D #2)
Noise 3 (random)
Envelope 3
Sense (read only)
Note: Special Voice Features
(TEST, RING MOD. SYNC)
are omitted from the above diagram.
54297
54298
54299
54300
52