View Full Version : Homebrew DH485 PIC?
June 5th, 2002, 02:01 PM
I would like to make my own PIC interface module for RS232 to DH485. Has anyone ever seen or heard of detailed documentation that would help me out? If I could get a schematic, I could lay my own board out, but I have not been able to find anything detailing the DH485 protocol specifications. I have a PIC I use at work, but I think it would be a cool project, not to mention the satisfaction of using one I built myself.
June 5th, 2002, 02:23 PM
Do a search of the site for this topic. This has come up a lot....
June 5th, 2002, 02:37 PM
I have successfully used a Black Box converter IC624A-F with some minor wiring changes inside the converter. This works well going into a single SLC500, but when you try to plug it into an AIC module with multiple SLC's networked, it causes problems because of the TEN (transmit enable?) line.
I would be interested if you get a good solution to this.
June 6th, 2002, 04:55 AM
Thanx for the pointers guys, I Google searched the web numerous times and could never find anything. I was beginning to think I was the only one who ever wanted to do this...All of our machines run single SLC500's with Panelviews, and a couple of them run AB servodrives as well. I'm in the middle of building a standalone MP3 player using a Amtel microcontroller, so I won't be starting this project for another couple of months. Just getting some research done in preparation.
Dang boss thinks I should live at the plant 7 days a week :D
June 6th, 2002, 11:02 AM
Might want to try AB's Publication 1770-6.5.16 DF1 Protocol and Command Set. I used it to create an interface with Atmels 89C51 micro for my SLC 5/03 and ML 1200 units.
June 7th, 2002, 01:48 PM
Well.....I'm feeling kind of dense now. I searched the site for (*485) and got 11 hits, and nothing I was looking for. I tried searching the archives and got nothing at all. If the subject has come up numerous times, I cannot find it.
ROBO, what are you using the Atmel micro for? It sounds interesting.
June 7th, 2002, 02:43 PM
He means search the other PLCs.net forum archives:
You're new. The above site was in operation for years, and the topic did come up (although in a quick search, I couldn't find it). This site/server opened up in April. But Phil hasn't moved the archives from there to here yet (a huge task, I'm sure).
But more than 11 hits on 485 or PIC, for sure. Good luck!