No One Cares

Kinda cool 72x6 LED matrix no one cares about

Serial commands

Syntax

Command syntax is made as compact as possible

Example: CMD<ahello<b123/

• CMD – command name. Command names always consist of three uppercase characters
• <a – first argument key. All argument keys begin with < and consist of only one lowercase character
• hello – first argument value
• <b – second argument key
• 123 – second argument value
• / – slash is required at the end of the command

Reserved symbols:

• <
• /

Reserved argument keys:

• d (argument derived from another piece of hardware code)

Reserved keywords:

• %IS% (value exists)
• %NONE% (value doesn't exist)
• %SCR% (scrolling animation)
• %BLI% (blinking animation)
• %RND% (random color)
• %CHRND% (random color of every character)
• %TLL% (taillight coloring)

Data model

Command arguments values represent different data types. This is the reference

• Int – number: 123
• String – case insensitive piece of text excluding reserved keywords and keys: hello world
• Char – case insensitive character: F
• ExBool – gets intepreted as true if argument is present in the command.
• Color – rgb representation of the color: Int,Int,Int / random color: %RND% / char random coloring: %CHRND% / tailight coloring: %TLL%
• Animation – scrolling: %SCR% / blinking: %BLI%
• Time – time in H,M,S,D,M,Y format: Int,Int,Int,Int,Int,Int
• CCPS – covey's compressed pixel sequence string: C>3RRGBWA>6
• Error – error code string

Command list

RTX – display text

Required arguments:

• t: String – text to display
• c: Color – color of the text

Optional arguments:

• i: ExBool – whether to display inout animation
• a: Animation – animation to apply
• e: Int – animation counter delay (1-10)

Optional return:

• Error ER011/ER012/ER021

ACH – append char

Required arguments:

• h: Char – char to append
• c: Color – color of the matrix

Optional return:

• Error ER011/ER012/ER021/ER041

CPS – draw CCPS

Required arguments:

• s: CCPS – sequence to draw

Optional return:

• Error ER011/ER012/ER021/ER051/ER052

CLK – display clock

Required arguments:

• t: Time – time to sync

Optional return:

• Error ER011/ER012/ER021

BRT – set brightness

Required arguments:

• v: Int – value (4-255)

Optional return:

• Error ER011/ER012/ER021

PNG – ACK the sender

Guaranteed return:

• String – constant pong message

CLR – clear matrix

CCPS

Covey's Compressed Pixel Sequence – the most compact way of filling the matrix I could work out

Syntax

PSs get drawn on a pixel-by-pixel basis. So, to draw something, an ordered list of instructions must be set to the device.

Each instruction is either a Custom Color, Default Color or Set.

Every Int must have a trailing comma if followed by another Int

Custom Color

Custom Color is a set of R, G and B values. Each value is either an Int, an f key, which represents full value (255), or an e key, which represents empty value (0).

Examples:

• 139ef – violet-colored pixel (gets interpreted as 139, 0, 255)
• f165e – orange-colored pixel (gets interpreted as 255, 165, 0)

Default Color

Default Color is one of the default presets, presented as a Key.

Keys:

• W (white) – 255, 255, 255 pixel
• N (none) – 0, 0, 0 pixel
• A (alpha) – skip this pixel. If anything was previously displayed on the matrix, it won't be overlapped
• R (red) – 255, 0, 0 pixel
• G (green) – 0, 255, 0 pixel
• B (blue) – 0, 0, 255 pixel
• C (cyan) – 0, 255, 255 pixel
• M (magenta) – 255, 0, 255 pixel
• Y (yellow) – 255, 255, 0 pixel

Set

Set is a repeated instruction. Each set consists of either a Custom Color or Default Color instruction followed by < key, and either an Int, representing the number of repeats, or an i key, which leads to drawing an instruction until the end of matrix. Any instruction after >i gets ignored.

Examples:

• 139ef>120 – violet-colored pixel, drawn 120 times
• f165e>i – orange-colored pixel, drawn until the end of matrix
• R>9 – red-colored pixel, drawn 9 times

NB: Sets don't make sence when a Default Color instruction should be drawn less than 4 times, as their definition in this case takes 3 characters.

Sequence examples

• WWRBB – draw two white, one red and two blue pixels
• NNf165,e – draw two black pixels, followed by an orange one
• R>100AAG>50 – draw 100 red pixels, skip two and draw 50 green pixels
• f192,203>100N>i – draw 100 pink pixels, draw the remaining in black
• R>72,f100e>72Y>72G>72B>72,139ef>72 – draw LGBT flag (change 72 to number of pixels in a row)

Error codes list

Error codes are returned by some functions if they fail to properly execute. Here's the reference

• ER011 – unexpected '1' selector while parsing command arguments
• ER012 – unexpected '2' selector while parsing command arguments
• ER021 – required argument not served
• ER031 – unknown command
• ER032 – unknown routine
• ER033 – unknown CCPS instruction
• ER041 – type error: expected Char
• ER051 – corrupted CCPS: unexpected i
• ER052 – corrupted CCPS: unexpected <