User Tools

Site Tools


x0x:digitalsequencer

The Digital Sequencer

Schematic Overview:Sequencer

Inputs:
None

Outputs:
VoltageControlledOscillator: Note, Slide, EnvelopeGenerator: Gate, Accent MidiAndSync: Midi In, Midi Out, Sync In, Sync Out

The sequencer made up of 2 primary sections, the MicroProcessor and the IO system of the sequencer.

The Microprocessor and EPROM

Input Section

Switches

The input from the switches are sent to the 3 74hc165 ICs (IC16, IC17 and IC18) which are parallel to serial converters. The serial data is sent to the MicroProcessor via the SPL_OUT line. The output from IC16 is daisy chained to IC17, which is daisy chained to IC18.

IC 17 IC 18 IC 16
SwitchFunction SwitchFunction SwitchFunction
6 Prev 5 Next 14 Done
7 C# 15 Run/Stop 21 G
8 D# 16 Chain 22 A
9 F# 17 C 23 B
10 G# 18 D 24 C
11 A# 19 E 25 Rest
12 Down 20 F 26 Accent
13 Up (tempo switch) 27 Stop

Tempo

Rotary Switches

LEDs (Output Section)

The LEDs are controled by Serial input into 5 74hc595 ICs (IC4, IC5, IC6, IC7 and IC8) which are serial to parallel converters. They are daisychained like so: IC4 → IC5 → IC7 → IC6 → 1C8.

Note: The LEDs and resisitors need to be linked up to their respective ICs, however, it is difficult to descern which goes where from the schematic.

LED Resistor - LED Resistor
1234-21246
2237-22248
3241-23249
4242-24258
5243-25265
6244-26264
7250-27203
8251-28229
9252-29228
10253-30227
11256-31223
12260-32222
13261-33221
14262-34217
15266-35215
16267-36213
17268-37211
18238-38208
19239-39205
20245-40204

Thanks to Maxtim for providing these values

/home/ladyada/public_html/wiki/data/pages/x0x/digitalsequencer.txt · Last modified: 2016/01/28 18:05 (external edit)