IchigoJam – Single ARM chip PC with Video and Keyboard support


PC

Everyone who has made their first steps with Apple ][, BBC micro, or Commodore 64 remembers the BASIC language, which nowadays is used by almost no one.

A few days ago, I was directed to an interesting project named IchigoJam BASIC. It was made in Japan and it was about creating a small computer with a BASIC interpreter, made on single LPC1114 Cortex-M0 ARM controller from NXP with only 32KB of Flash and 4KB of RAM.

Ichigo means Strawberry, so this keeps the tradition PCs to be named on fruits.

Although it is built on tiny resources, IchigoJam BASIC has quite an impressive list of commands including I2C read and write!

The schematic is quite simple.

The composite video generation is made via a couple of resistors, and the keyboard is connected with a simple USB-A connector, so with just a few components you have a small personal computer!

And this is not everything, the same hardware has firmware for Javascript called IchigoLatte , for Ruby called IchigoRuby, for IchigoFORTH and here.

On top of this, if you want to try IchigoBASIC you can do it on the web. How cool is that?

Needless to say, I wanted to try this project. I choose our LPC-H1114 board as it has almost everything already pre-soldered.

I had to connect:

for power supply:

LPC-H1114.pin50 – to GND
LPC-H1114.pin49 – PWR to +5V DC

for firmware update:

LPC-H1114.pin46 – to USB-Serial Tx
LPC-H1114.pin47 – to USB-Serial Rx
LPC-H1114.pin4  – to GND

for Videop output

LPC-H1114.pin27 – 470 ohm to video connector
LPC-H1114.pin28 – 100 ohm to video connector

for USB keyboard connector:

LPC-H1114.pin23 – DP
LPC-H1114.pin14 – DM

You can update the firmware using the instructions here.

If you did everything correctly when you apply the power supply you will see on the monitor the text “IchigoJam BASIC 1.4.2 by jig.jp”:

IchigoJam

Then you can use the keyboard to write your program!

You can repeat the project with quick dirty wire connections like I did:

LPC

What you need is a LPC-H1114, a Video RCA jack, a USB connector for the keyboard, a small monitor, a keyboard, and some jumper wires.

This project would be a very good fit for some next Soldering workshop as it has few components but it completes a fully functional BASIC/Ruby/JavaScript/Forth computer.

With the current state of COVID-19 probably TuxCon would be postponed for the Autumn, so there is plenty of time to make a small PCB for soldering 🙂

IchigoBASIC has a button, an LED, plays music on a buzzer and you have access to 4 Digital Inputs and 6 Digital outputs and I2C interface connector.

Too bad most of the educational stuff is in Japanese and needs translation.

 

5 Comments (+add yours?)

  1. scottstensland
    Mar 24, 2020 @ 17:49:22

    this blog is impossible to read … its light colored text on a light yellow backgound … wonderful content though

    Reply

  2. SK
    Mar 24, 2020 @ 22:38:17

    The schematic link actually leads to the BASIC listing and I can’t seem to find my way to the schema on their website, can you help 🙂

    Reply

  3. ukscone
    Mar 25, 2020 @ 06:44:23

    If you dig around on kidspod.com you’ll find quite a lot of BASIC programs to type-in or use with micjuice/mixjack add-on. i’ve also knocked up a very mickey mouse 1st cut of a python program (very buggy and needs some fiddling with to match “spec” ) to download things to the ichigodake/ichigojam https://gist.github.com/ukscone/790013d13d38f52c97c4dbb053508d4c
    most of the documentation translate pretty well using google translate especially if turned on to always translate especially on https://15jamrecipe.jimdofree.com/

    Reply

  4. Juergen Pintaske
    Mar 25, 2020 @ 20:46:38

    If people want more, I collected non-Japanese documentation including OLIMEX both boards in a book https://www.amazon.co.uk/gp/product/1079519238/ref=dbs_a_def_rwt_bibl_vppi_i29 in there are the commands explained, and a long list of short examples. There are 2 facebook pages English and Japanese. If you use google to translate it works quite well.

    Reply

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