Pretzel Logic

Pretzel Logic is a 4 bit to 16 step addressable analogue sequencer based on the CD4514 SMD IC, that outputs gates.

In the past we had a product named Cryptograf, but had to discontinued it a few years ago due to chip shortages of the IC it was based on. Now, we have secured a quantity of CD4514 SMD IC's and can offer this new module based on that IC and SMD daughterboards.

Pretzel Logic is an update of the Cryprograf, outputting gates rather than CVs.
Pretzel Logic is also proving ground for some fancy new circuitry which will at some point in the future allow us to build the ultimate iteration of what a module based around a CD4514 can do. But that’s for later. Let’s talk more about Pretzel Logic.

Pretzel Logic is a 4 bit to 16 step addressable analogue sequencer which outputs gates.
Each of it’s 16 steps can be addressed in any order for ultimate creative flexibility.
Pretzel Logic pairs nicely with Polygraf, High Towers and Akropoli; together they make a powerful combination.

Pretzel Logic features 4 address inputs, 1, 2, 4 and 8, each of which has an associated input socket as well as a 3 position state switch which allows each address input to be held high, respond to input signals, or held low.

Each input has two status LEDs. The red LED displays the signal present at the input socket, while the green LED displays the status of the address input.
The combination of signals present at the input sockets, together with the positions of the state switches allows Pretzel Logic to have 16 different output states, numbered from 0 through to 15.

The output state of Pretzel Logic can be ascertained by observing which of the 4 address inputs are high, for example:

If no green status LEDs are on, Pretzel Logic is in output state 0
If green status LED 4 is on, Pretzel Logic is in output state 4
If green status LEDs 1, 2 and 4 are on, Pretzel Logic is in output state 7
If green status LEDs 2 and 8 are on, Pretzel Logic is in output state 10
…..and so forth.

The input sockets may be addressed by various external modules, for example:
FC Pocket Calculator, FC High Towers, or similar clock dividers with multiple outputs from other manufacturers.
FC Polygraf or similar grid editors from other manufacturers.
FC Little Melody, Akropoli or similar.
Clearly, we here at FC would nudge you towards other FC products as the most flexible way to address Pretzel Logic. They were designed to be together and share a deep and enduring love for each other. This successful partnership allows Pretzel Logic to be addressed in many ways, for example:

Forwards from 0 through to 15
Backwards from 15 through to 0
By repeating rows, or by repeating columns
Asequentially, in any order you choose

As Polygraf is capable of storing many user patterns which themselves are selectable by CV, multiple chained patterns are possible. Furthermore, we accept that users will discover their own unique combinations of FC and third party modules to address Pretzel Logic, always bearing in mind that at any time the status of any of the 4 input sockets may be overridden by the 4 state switches.

Latch function

Pretzel Logic may be latched manually via the Latch toggle switch, or externally via the Latch input. When Pretzel Logic is latched, the last output state to go high is held until Pretzel Logic is unlatched.

CD4514 through hole are getting harder to find, although CD4514 SMD are widely available. There are three choices here:

1) Souce your own CD4514 through hole. Take care of fakes out there.
2) Use one of our CD4514 SMD and solder it directly to the PCB (recommended for skilled DIYers)
3) Use one of our CD4514 on daughterboard. These are CD4514 SMD that we have soldered onto a tiny daughterboard PCB and added headers to. We then test them in an assembled Pretzel Logic. They are a drop-in replacement for CD4514 through hole. For these, we recommend that you solder the 24 pin socket 0.6” to the PCB then plug the CD4514 on daughterboard into it.
4) Module is avaliable as fully built, DIY FULL Kit, DIY PCB's & Panel, Bye CD4514 on Daughterboard, by CD4514 SMB.

https://frequencycentral.co.uk/product/pretzel-logic/