Shift Register Stages
After starting to build some drum modules, but not having built a drum sequencer yet, I cast about the modular world to see what the simplest way to sequence some drums would be given what I had built already. Happily, I found that the Pulses expansion for the Turing Machine was almost purpose built to be a mini drum sequencer.
Shift Register Stages is a clone of Music Thing Modular’s Turing Machine Pulses expander. This module connects to the Shift Register Sequencer via a ribbon cable and produces a series of clock signals based on the state of the shift register.
The design of the module is ridiculously simple, it’s just a bunch of resistors, jacks, light emitting diodes (for the blinking light effects), and a single CD4081 AND Gate to do the four outputs which are based on multiple stages being active simultaneously.
| Name | Signal type | Notes | |
|---|---|---|---|
| Out | 1 | Clock | Outputs when the first stage of the shift register is high |
| Out | 2 | Clock | Outputs when the second stage of the shift register is high |
| Out | 3 | Clock | Outputs when the third stage of the shift register is high |
| Out | 4 | Clock | Outputs when the fourth stage of the shift register is high |
| Out | 5 | Clock | Outputs when the fifth stage of the shift register is high |
| Out | 6 | Clock | Outputs when the sixth stage of the shift register is high |
| Out | 7 | Clock | Outputs when the seventh stage of the shift register is high |
| Out | 1&2 | Clock | Outputs when the first and second stages of the shift register are both high |
| Out | 2&4 | Clock | Outputs when the second and fourth stages of the shift register are both high |
| Out | 4&7 | Clock | Outputs when the fourth and seventh stages of the shift register are both high |
| Out | 1&2&4&7 | Clock | Outputs when the first, second, fourth, and seventh stages of the shift register are all high |
