Microwriter revisited

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I'm taking a break from Test Equipment, and resuming a project that has been on hold for a couple of years.

It's a home brewed compact one-hand chorded keyboard inspired by the Microwriter.

I started the project using an Atmel ATMega8 hosted on SimmStick hardware. My tools for software development were primitive. WinAVR was still in its infancy, so like most Atmel developers I used AVR Studio and programmed in assembler or programmed in BASIC using Bascom from MCS Electronics.

I decided to use I2C to connect the micro controller to the keypad and LCD display. Driving I2C in assembler was a pain, and writing the keyboard handling in Basic was positively soul-destroying. I decided to wait until technology had improved enough to make the project enjoyable.

Fast forward two years. The Arduino offers an affordable hardware platform and an easy-to-use IDE. The main challenge is the keyboard itself; I'm going to experiment with QTC pills which look perfect for this sort of application.

Once I've put together a prototype keyboard I can drive it using an I2C board, an Arduino and an I2C LCD display. I'll use the I2C data logger to hold text.

Comments

  1. Cynical_cell15 September 2014 at 17:17

    Well? What happened? I'd love to do this but am too busy...

    ReplyDelete
  2. Romilly Cocking15 September 2014 at 17:32

    The keyboard was the problem. I eventually built one using microswitches, and it worked, but was literally too painful to use.

    These days I'd probably use capacitive sensors. I may resurrect this some day, but I have other projects stacked up for the foreseeable future.

    ReplyDelete
  3. Cynical_cell26 November 2014 at 14:21

    Interesting. The clicky keyboard was a great strength of the old microwriter, but used to enrage my neighbours.

    If I was making one now I'd use a glove with piezo sensors...

    ReplyDelete
  4. Ken Boak15 January 2015 at 19:07

    Hi Romilly,

    I built a microwriter style keyboard for a project to aid a disabled person some years back based on a PIC. I found some nice rocker style keyswitches that are easy on the finger tips. I must also resurect this project and base it on the Arduino or Pi.

    ReplyDelete

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