ASCII mode?

[paologaleotti]

Hello, me and my team are about to use this lib in production for a big project, but we noticed that ASCII mode is lacking.

Will it be possible to implement it? I don't think it's hard, maybe i'm missing something but i don't see a way of using ASCII right now.

[qba73]

@paologaleotti would you be willing to implement the feature and send PR?

[simonvetter]

Hi Paolo,

ASCII mode is indeed missing... mostly because I have yet to find a device in the wild that 1) supports it, 2) doesn't support RTU mode and 3) is configured for ASCII by default.

You're right that implementing an ASCII transport should be fairly straightforward. Now testing it in multiple configurations, with different device and vendor implementations would be a harder task IMO. I'd have to get my hands on a lot of ASCII-capable hardware to test and validate all current opcodes, and this really isn't high on my list of priorities.

Out of interest, what devices are you targeting? Do those not support RTU, or is ASCII mode a choice on your part? Not questioning your motive or anything, I'm merely trying to understand where you're coming from.

[d21d3q]

I have vibe coded ASCII mode on my fork.

I've also added e2e test suite against pymodbus server. So it is tested only on emulated serial (using socat).