A Programming Language for a Portable Development System

Prototyping with Arduino and compatibles is fairly easy, especially when it comes to the hardware.  A breadboard simplifies things quite a bit.  A few months ago, I realized that I did not have any, so I purchased one, in a kit, on Amazon from a company called Elagoo. The kit, for about sixteen dollars (US) contained a lot of parts and the breadboard. Well, the board is fairly small, so I decided to create a portable workspace and mount the breadboard, an Arduino UNO R3 clone, a 2 x 16 LCD and some cord organizers.  It works great, and I can take my project around. Nice.  Problem, though, is that I still need to be tethered to the computer in order to write code.

WP_20161001_18_38_08_Pro_LI (2)This got me thinking…could I come up with a small but easy to use interface language that could be coded with nothing more than a 12 key keypad?

The answer is yes.  So, I have come up with an initial set of opcodes for programming with nothing more than what is on my workspace. 

This language would more resemble CHIP-8 than, say, the Arduino language.  Commands, statements and functions all use a single byte but can have one or more subsequent values for parameters.

The tables below outline the main features. The keypad I am using (because it was less than a buck) does not have enough keys for full hexadecimal, so I had to improvise. Still working on a scheme to allow alphanumeric entry without connecting a full ASCII keyboard.  For now, the language will be limited to reading sensors, accepting decimal (though integer only) numbers. No video, serial out to the 2×16 LCD or a Bluetooth module.

For the tables, the first column is the opcode, second is what the opcode does, third is any parameter( s ) necessary and the last is a description.

Assignment:

01

Let

Var (00-0F)

Value (00-FF)

Conditionals:

02

IF

Var (00-0F)

01 is equal, 02 is <, 03 is >, 04 is <>

03

Jump if true

Addr (00-FF)

 

Program Flow:

04

Goto

Addr (00-FF)

Transfer control to address

05

Call

Addr (00-FF)

Call a subroutine

06

Return

   

07

End

 

Ends program

Input/Output

10

Inkey

Var (00-0F)

Gets input from the keyboard

11

Out

Var (00-0F)

Outputs a value

12

Temp

Var (00-0F)

Gets a reading from the temperature sensor

13

Pinset

00-FF

Send a value to pin

14

Pinread

00-FF

Get a value from pin

15

Xfer Pin

Var (00-0F)

Transfers value from read pin to variable

I would envision the interpreter being fairly small, so it may be possible to integrate several libraries for the more popular sensors, like DHT-11 temp sensor and others.

So, what do you think?  Is this something of interest? Please post your thoughts in the comments below.