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RC: LED Color Table: EXP Bus Command Reference

Understanding EXP board addressing

This command is used with FAST Expansion and FAST breakout boards via a FAST Serial Protocol (FSP) connection to the EXP Bus. Please read the EXP Overview to understand the operation of these commands and addresses.

This command is used to set individual RGB LEDs to colors from a lookup table. You can chain together multiple LEDs in a single command.

Note that there is also a binary version of this command, RC:, which might be more appropriate for your use case.

Command Syntax

RI:<index><entry>[,<index><entry>...]<cr>

<index>

This is the LED number for the LED you want to update. Individual LEDs are accessed via hex 00 - 7F (0-127) since that's the max LEDs that can be attached to a single breakout board.

New in firmware 0.20:

You can also use mapped LED blocks which you configured via the LM: command. In this case, all the LEDs in that set will be updated to the same color as if they were a single LED.

If LED maps have previously been created on the expansion board targetted, then LED indexes 80-FF correspond to the mapped LED sets.

<entry>

Each color table entry is a single byte, in the range of 0-255 (hex 00 - FF).

Default Color Table

The color table for each expansion board can be modified using the RT: command. At power on the color table is initialized to a standard palette with a range of colors.

Examples

You can update more than one LED at a time with this command by putting commas between each LED.

For example, to update three LEDs:

  • LED 01 - entry 0x10 (red)
  • LED 04 - entry 0x60 (orange)
  • LED 10 - entry 0x4E (purple)

The command would look like this:

RI:0110,0460,104E<CR>

Breaking it down:

  • RI: command name
  • 0110 set LED 01 to 10
  • 0460 set LED 04 to 60
  • 104E set LED 10 to 4E
  • <CR> at the end

If you have a global fade rate set (via a previously-sent RF: command for the board the LEDs are attached to), then the LEDs will fade to that rate over the given time.

Return Response

None

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