SR61 - MicroMod 60% Custom Keyboard PCB

Featuring SparkFun's MicroMod Processor Boards

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Very happy to announce that PCBWay has gratefully sponsored the production of the first 5 RevA PCBs, and a partial assembly service (all but the USB-C, Hot-Swap Sockets, JST-ph4 & SK6812's), for this project.

Thank you PCBWay!

Please follow the updates to this production process on the changelog page.

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Published as Open Source, under a Creative Commons Share-alike 4.0 International.

Rev B  

👍 WORKING, OK TO BUILD

• PDF Schematic ¹

• EAGLE PCB

• EAGLE Schematic

• Notes:

  • Keymap Working on both STM32 and PR2040
  • (Optional EEPROM not tested yet)

¹ = RevB.1 schematic is here

Rev A  

⚠ Do not use this revision, it has terminal flaws.

• PDF Schematic
• EAGLE PCB ²
• EAGLE Schematic ²

² = to access these files please use the Github history

QMK code:

• https://github.com/Tecsmith/sr61-keyboard-qmk
• USB Identifier registered with pid.codes = 1209/7672

Layout

• KLE link

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Features

SR61-MicroMod - using SparkFun MicroMod STM32 or RP2040 M.2 module

Core Design Elements

• 60% form factor

  • Design to be compatible with GH60/HK60 cases
  • Also compatible with Anne Pro 2 cases (drop in QMK replacement for existing AP2's or AP2 cases) [Removal of battery and minor case cut in the battery compartment required.]
  • MicroMod positioned in case "battery compartment" space.

• QMK + VIA default f/w

  • Wired only (no wireless)
  • Default key-maps for Mac users

• User choice of microcontroller

  • STM32 Processor

    • ARM Cortex-M4, 168MHz, 1MB Flash, 192kB SRAM
    • https://github.com/Tecsmith/sr61-keyboard-qmk

  • RP2040 Processor

    • ARM Cortex-M0+, 133MHz, 128Mb Flash (16MB external), 264kB SRAM in six banks

• USB-C (left side)

  ... but also optional JST connector for ai03 Unified C3 Daughterboard

• ESD, Over Voltage and Over Current protection

  ... and cable shield noise filter

• Hot-swap, 5 pin switch slots

• PCB mounted stabs compatibility

• Dual ANSI / ISO layout support

• 61-Key (ANSI) / 62-Key (ISO) Layout [1.25, 1.25, 1.25, 6.25, 1.25, 1.25, 1.25, 1.25] bottom row (a.k.a. "Poker" / "POK3R" Layout)

• Limited RGB LEDs (SK6812 mini-E)

  • RGB Caps Lock Indicator

  • North facing RGB's under the 5, 6, 7 & 8 keys for layer indicator

  • WS2812/SK6812 breakout for optional external LEDs

• Spare GPIO pins (52 & 63) breakout for expansion

  ... e.g., add speaker

• Both [Reset] and [Boot] buttons (as per MicroMod ref. design)

  ... plus under space-bar Boot pins for bootload without disassembly (press while inserting cable for bootloader function)

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Made with ❤️ by Silvino Rodrigues