Unicomp Mini Model M matrix simulator (WIP)
This interactive tool simulates the key-matrix of a Unicomp Mini Model M so that you can test if possible key combinations work without needing to test on a physical keyboard. Model M keyboards are all fundamentally two-key rollover (2KRO) due to the use of a membrane assembly, but this doesn't mean Model Ms cannot register more than 2 keys unlike popular belief. This tool demonstrates this and can allow you to see if a given Model M key-matrix would be suitable for your needs.
Disclaimer & notes
This tool is intended to be a guideline only. The results from any input are based on physical key-matrix data only and doesn't take into account firmware (ie, differing deghosting algorithm implementations or bugs/quirks). If you're using this tool as part of a purchasing decision, if possible, it would be prudent to try verifying results on a real keyboard someone you know has or ask on /r/modelm subreddit. The tool is also best viewed on desktop.
Only UK English functional layout is available for the ISO simulator at this time
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Firmware caution: A 3-key combination that may or may not be problematic depending on keyboard's firmware. A custom QMK-based controller would probably be fine with these, but IBM/Lexmark/Unicomp native firmware may not. |
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Hardware block: A N-key combination that will block in any circumstance due to the matrix's design. There is nothing you can do about these since they're a fundamental key-matrix limitation. |
Matrix
This is a tabular representation of the data used by the simulator above. A keyboard matrix is constructed from a series of columns (X-axis) and rows (Y-axis) whose intersections are used for key assignment. Such matrices allows a large number of keys to be driven by relatively few traces, as opposed to each key requiring its own circuit.
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | A | B | C | D | E | F | G | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | Grv | Esc | 5 | RShiftHid | F2 | F3 | F4 | P | Lalt | Enter | - | ||||||
| 1 | Caps | LShiftHid | Q | 6 | F5 | EnterHid | Rctrl | RShift | - | ||||||||
| 2 | S | D | F1 | F | G | Z | C | X | V | B | A | Tab | - | ||||
| 3 | 1 | Y | F6 | Lwin | - | ||||||||||||
| 4 | 4 | O | F7 | Lctrl | LShift | - | |||||||||||
| 5 | W | 7 | F8 | [ | Rwin | - | |||||||||||
| 6 | 2 | U | F9 | = | F10 | F11 | - | PrtScrn | - | ||||||||
| 7 | 3 | I | F12 | BackspcHid | ScrLck | - | |||||||||||
| 8 | T | 0 | Backspace | Up | End | Ins | - | ||||||||||
| 9 | R | Ralt | Left | 9 | BackSlash | Home | - | ||||||||||
| A | Space | E | Rmenu | 8 | ] | Right | Down | Pgup | PgDn | - | |||||||
| B | M | " | " | . | FwSlash | H | K | J | L | ; | N | ' | Del | PauseBr |
- Many thanks to Purdea Andrei (/u/_pandrew, purdeaandrei) for providing the IBM Enhanced Keyboard, Unicomp PC 122, Unicomp EnduraPro/Ultra Classic and Unicomp Mini Model M matrices and providing technical assistance.
- Many thanks to whiskerbiskit for helping to crack the Unicomp Mini Model M matrix.
- phosphorglow's IBM Space Saving Keyboard matrix was used for the IBM Space Saving Keyboard matrix simulator.