Build A Scene (A)
The A command allows new channel:value combinations to be stacked on the existing DMX output universe. This command adds to what's currently being output. In Photoshop, it's similar to creating a new layer. Nothing below is affected, the A command just adds new channel:value information to the existing scene.
If you're starting from scratch or building your own driver, use the G (group) command instead. It's easier to design with because leading zeroes are omitted and the syntax is more powerful.
A is a capital A
XXX, AAA, CCC are three digit DMX channel numbers with range [001 512]
YYY, BBB, DDD are three digit channel values with range [000 255]
TTT is a three digit time value, in tenths of a second, range [000 999]
For ‘A’ commands, the channel:value information contained in each string adds to data in the DMX output buffer. Higher values take precedence. Thus, lighting data may be added to existing scenes a few channels at a time. In a photo editing application, this process would be similar to adding layers to an image.
Leading zeros are required.
If a channel is not specifically mentioned in an A command, its value remains the same as it as before the command was processed.
If the following commands were transmitted:
... the DMX output buffer would have the following values:
CH1 : 100
CH2 : 255
CH10 : 128
CH11 : 127 CH12 : 126 CH7 : 10