migration from 16F876a to 18F25k22

[MOUNTAIN747]

I have a project that I have built for the farm to extract the moisture content of grain in the silos. The project is working well. I would like to add a RS485 comm ( Master, 5 Slaves ) to the project to communicate with all silos. The current boards use PIC16F876a. I am having difficulty with DT_INT and HSERIN routines using the 16F876a. After reading all 17 pages of DT_INT’s I think it would be much easier to upgrade my processor to 18F to get the quality of comm that I need. I am considering a 18F25k22 because it should do the job and because I would like to use this processors features in future projects. I have not yet worked with this processor and I am wondering what changes I will have to make to my current code in order to use it. Comments please? Would this be a good choice for upgrade or is there another processor that would be better for upgrade from 16F876a?

Thanks!

Wayne

[Demon]

Off the top of my head, CONFIGs are more complicated with 18F family.

You might also want to consider moving to MPASM if you haven't already.

Robert

EDIT: Off-hand 18F PICs are superior to the 16F family, but it's hard to tell you if that PIC is the best for you, especially if we don't know exactly what features you want now, and what you will need in the future. Microchip does have comparison and migration information, you might want to start here:
http://www.microchip.com/stellent/id...GE&nodeId=2661

Also, if you intend on migrating to PBP 3.0 as well, things have changed a bit too:
http://www.picbasic.co.uk/forum/show...963#post110963

[MOUNTAIN747]

Demon, Thanks for responding. I have considered the change in Config’s on the 18F’s, the pin outs seem to be the same so the 18F25k22 should replace the 16F876a with only minor changes. The extra memory will also come in handy as the code seems to always grow, I think there’s some kind of natural law that says that has to happen.
I haven’t jumped to PBP3 yet (which supports 18F25k22). PBP2.6 has the support files for 25k20 and I think it would take just a few tweaks to create new files for the 25k22. PBP3 Does Look Good and I think DT_INT can be run without MPASM. Has anyone put together a list of difficulties in migrating from 2.6 to 3 while working with file created in 2.6?

[Demon]

More clutter with more available space also applies to basements, and in double for garages.

I'm still on 2.60C, but you'll have a good list of migration errors from me when I'm forced to make the jump.

Consider switching to MPASM as a small step, it's just a download and then pointing to that library from within Microcode Studio. I downloaded the entire MPLAB Suite, but only point to MPASM.

And you're going to need MPASM if you ever do USB.

Robert

[ScaleRobotics]

I believe DT_INTS requires MPASM. PBP3 require MPASM or MPASMx. PBP3 was a pretty easy migration. I think some of the install instructions pretty much cover it, but there are a few things. Here is a migration document: http://pbp3.com/downloads/Migrating%...0to%20PBP3.pdf

[MOUNTAIN747]

Thanks guys for your comments and links!
Don’t you hate those new learning curves ? Dang it, once I think I just about got the hang of one piece of software I need to change. I don’t have a problem with MPLAB, in the later part of the last century I spent a couple of years playing with ASM. It’s just that PBP takes much of the work out of it! Migrating just means down time. I’m sure I’ll go PBP3 once I figure out what upgrade I need and if I need to get a new MCS. By the way, I see a Compiler V3 on Reynolds web site. What is V3? Have ether of you tried to add your own files to MCS+ to gain a new processor? OOPs, maybe I shouldn’t ask that question…

One more thing, I think I've seen post by both of you doing work with graphic LCD's. I need to get into these LCD if for no other reason that I need more screan space for messages. I don't need touch screen but I do need something in the range of a 5 to 6 inch display. any suggestions on brands maybe with some ASKII maps on board?
Thanks!

Wayne

[Demon]

You don't have to use MPLAB, I just downloaded it to have a recent version of MPASM. You don't have to use MPASM directly either, you keep on working in PIC Basic Pro (MPASM is used in place of the default assembler in background).

You don't have to go to PBP 3.0 either if you're happy with what you have. I'm on PBP 2.60C, Microcode Studio Plus v2.2.1.1 using 18F4550 with USB and I'm quite happy!

It's just that some new features need MPASM to function, like USB and DT Interrupts.

Sorry, I haven't added a new processor in MCS. And no, as far as I know it's not forbidden to discuss that subject. I have seen others post about doing it, I don't think they included details though.

5-6 inch LCDs, I haven't looked recently but those buggers weren't coming down in price very fast. Something like $80-100 USD several years ago, ebay is a good place to get an idea what they go for now. Particular model, I worked with one LCD more than the other demos I received. I'll have to do some digging.

Robert

EDIT: What about something like this?