RW: Set White Channel command, EXP Bus Protocol 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 the white channel for individual RGBW LEDs. You can chain together multiple LEDs and values in a single command.
Note that there is also a binary version of this command, RZ:, which might be more appropriate for your use case.
Command Syntax¶
RW:<index><w>[,<index><w>...]<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.
<w>¶
Value of the white channel as an ASCII hex number, in the range of 0-255 (0x00 - 0xFF hex). This is combined with the index into a 2 byte / 4 character hex argument.
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 - no white (00)
- LED 24 - half white (80)
- LED 7A - full white (ff)
The command would look like this:
RW:0100,2480,7AFF<CR>
Breaking it down:
RW:command name0100set LED 01 white channel to 002480set LED 24 white channel to 807AFFset LED 7A white channel to FF<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 new color over the given time.
Return Response¶
None
N or > jump the next page, P or < for previous, search with S or ?