I want to make a DMX512 transmitter with a STM32F103 using HAL, CubeMX.
I found some documentation like here about the protocol: Lighting-Control-using-DMX512-protocol-on-STM32.
Sadly it does not show code, however, I have some questions about the protocol itself mainly:
These are excerpts from chapter 2 from the manual:
- "MARK" time between slots: 0 - <1.00 s ... so if the minimum time is 0, why not leave it out completely?
- "MARK" before BREAK (MBB): 0 - <1.00 s ... same here? why bother to 'implement' it?
- Also in the diagram START TIME is mentioned, but there are no timing requirements for it... how can I know what is allowed?
- In this GitHub file some code (non HAL, but STM32) is shown where there are many remarks about time critical functions, but according to Table 1 there is for most items max. 1 second time, this I would not call time critical. I know HAL/CubeMX tend to have quite a lot of overhead code, so I wonder if this will give problems.
If someone has more information about a DMX512 transmitter, preferably using HAL/CubeMX, I would like to hear about it (couldn't find any example/code).