dmx.c file

mewanchyna · Joined: 21 Nov 2005 Posts: 15 Location: Montreal, Canada

I know we have covered this topic. There has been a lot of discussion on this and unfortunately, there is no correct answer. I have tried the file that is supplied in the "drivers" folder, dmx.c. Other than being a software UART, it seems to have no provisions for being a DMX receiver. I thought there might be a switching of the "xmit" pin for bi directional use but it is not clear. Besides, I think that pin reacts as an output. Do I need to deal with interrupts myself or is this handled by the dmx.c file?

I am looking to make a simple DMX to single PWM. The PWM is working as expected but I cannot get a single byte of DMX. Has anyone got the DMX.c and DMX.h files working or are they buggy?? Thanks,

Mark

PS I am using CCS 5.11 and PIC16F887

temtronic · Posted: Sat Oct 15, 2016 12:41 pm

rcving DMX is rather simple...just use Google to find any of 3 or 4 dozen programs that do that.
The CCS dmx.c is a transmitter from what I recall.

Jay

Ttelmah · Joined: 11 Mar 2010 Posts: 19552

For the receiver, the UART is setup in ex_dmx_slave.c, which then loads the driver. Look at this.

The software UART is used by the transmit only.

mewanchyna · Joined: 21 Nov 2005 Posts: 15 Location: Montreal, Canada

Thanks for the responses. As it turns out it seems that version 5.011 doesn't have this example file in it's library. As Jay mentioned, I have already looked at so many versions of doing this that my head is spinning. Is there any way to get a copy of the ex_dmx_slave.c file?

Mark

Ttelmah · Joined: 11 Mar 2010 Posts: 19552

Talk to CCS.
Easiest honestly, upgrade the compiler. 5.011, is a rather early V5 compiler.

temtronic · Posted: Sun Oct 16, 2016 4:49 am

If you ask CCS nicely, they may send it to you. They actually sent me the entire examples folder eons ago when I went from 2.5xx to 3.5xx. Yeesh, that was eons ago.....

Or just let Google find working 'slave' or rcvr' code. I've seen lots over the years. Essentially it's nothing more than a serial 'setup', get the data string, parse and then do 'whatever'.

Jay