AVR developer needs PIC help

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View


I hate to bother everyone with sometihng that screams newbie, but I'm lost.

I decided I should broaden my horizons beyond the AVR line.  Very happy
with Atmel parts, but PICs have some attractive memory/pin count options
not present in the AVR line.  As well, seems lots of hobbyists want
designs using the PICs, as they have more DIP variants.

I went to microchip and ordered me a couple each of the
18F2620,18F4620,18F1320, and a couple 16F688 (nice memory for such a
small size part).

I'd been trolling via Google for a few weeks looking for stuff, but
after the purchase, I decided I really needed to grab the programmer
schematic (as I have a pending Digikey order) and see what I need for
the SW.  So, I figured, get the STK200/300 ISP schematic counterpart for
the PIC, grab a command line programmer equivalent to avrdude, and I'm set.

It's now many hours later, and I've been seen NOPPP (along with the
disclaimer from the developer to not build it), TLVP, THVP (Hi Byron), a
slew of programmers that need a programmed PIC to run, etc.  I'm also
drowning in a sea of different programmer SW options, many of which only
support certain programmers and/or PIC variants/families.

So, either the success of the PIC line is what is confusing me with so
many options, or what I desire is truly not available:

simple programmer that will handle ISP programming of 18F line for sure,
and 16F line would be nice.  I'm partial to simplistic STK200-like
designs that use the parallel port, but would consider $30-$40 if
commercial.  The $60-$100 options were too much to swallow for me.  USB
would be OK if SW support is good on target platforms.  Parallel
programmers seems to have the best support.  I saw the TLVP, which looks
pretty simple.  I couldn't verify what THVP buys me here, to warrant
finding a bigger wall wart.  For the SX parts, I bought the SX-Key,
which most people seem to support.  Is there a predominant ISP
programmer for the PIC line?

Linux and Win32 (XP) SW to drive said programmer (I use both platforms).
  Command line tools are preferred, as I like "make program" ala AVR-GCC
and friends.  I saw picprg, but I can't tell if it supports the 18F
series nor if it offers a cmd line mode.  Tait's FPP also didn't have
info on whether it handles 18F parts and if it would run under Win32
(XP), which guards access to the parallel port.

Maybe I am asking too much, and if so, let me know how close I can get
to what I want, if at all.  If I can't even get close, anyone interested
in some new-in-box 18F series PICs? :-)  I never dreamed it'd be this
hard to get started in PIC (And, I still need to find a C compiler...)
I suppose I'm just a spoiled AVR fanboy, but this seems hard to me.

Jim


Re: AVR developer needs PIC help



Quoted text here. Click to load it

I have sucessfully programmed the 16F688 and 18F2455 with a very simple
programmer.

The basic idea is given at http://www.finitesite.com/d3jsys/proghvp.html . (I
used a different buffer but I suppose you can use anything you want as long
as you are able to get 5 volts out(i.e., you can use TTL with pullup
resistors, etc...).


I used the parallel port and WinPic(http://www.qsl.net/dl4yhf/winpicpr.html )
and it seems to work prefectly as far as those two pics are concerned.
Write your code, assemble/compile it into a hex file, load it up in winpic
and tell it to program the pic and your done.  You will have to setup an
interface which tells winpic what parallel port pins are what. Its pretty
easy to do and explains it all in the help documents. I use

[Info]
[ProgrammerControlLines]
VppOnOff=!D2
VddOnOff=!D3

DataIn=ack
DataOutD7%
DataOutWhileReading=0
OutEnable=!D6

ClockOutD5%
ClkEnable=!D4

and have the outputs appropriately hooked up to the buffer and then to the
pic(the power pins control transistors which is necessary for the high
voltage need to program the pic).

(You can add more Programmer Control Lines to WinPic to control things such
as buttons and LEDS and such to add more functionality)

You would be supprised how easy it is so my advice is for you just to dive
right in.  Although I still have not yet been able to program the 18F4431
for some reason using the same method...

Some things to note are that in WinPic you need to select raise VDD before
VPP on some PICS(look at the timing diagrams for them to know... the 16F688
needs it raised after and the 18F2455 needs it raised before).

Probably the hardest part of it is getting the parallel port output... I had
to tear up an hold modem and rip its connector out and manually solder wires
to the pins so I could interface it with my breadboard... I then used hot
glue to secure the wires at the connection to the connector so they wouldn't
wiggle and short out... its not pretty but seems to work.

I'm sure you could easily do this in a weekend if you wanted and have the
parts.. its relatively easy connections(basicaly connect the dots).  You
will need about a 13V power supply though. I made a power supply that had 5,
12 and variable so it was pretty simple to use but if you know what a
voltage regulator is and how to use it then it shouldn't be much of a
problem.

Don't be scared to try it though... I had a lot of anxiety about it because
I was afraid I would screw up the pics... but it went relatively
smoothly(took me a couple of hours to do everything(excluding building the
PS)).  Another hint is that in WinPic you have to slow down the timing for
some pics.... for the 18F2455 I can use it at 1us and for the 16F688 it has
to be at 7us(you'll know what I'm talking about if you use winpic).

If you need any more help I'll step you through what I have to get you on
your way.

Jon



Re: AVR developer needs PIC help


Quoted text here. Click to load it
I saw that.  Byron's HLV programmer, but why it and not the LVP?

Quoted text here. Click to load it

This line concerns me (from the web page):
"Code memory size now up to 8192 words, data EEPROM memory up to 256 byte."

Seems like a 64kB 26XX would not work...

Quoted text here. Click to load it
Maybe this high voltage thing is common in PIC land.  I'm just worried
my ISP programmer would fall over my work, the HV would hit something,
and poof, there goes an IC.

Quoted text here. Click to load it
I appreciate.  I'm confident I can get things going, as I already
program AVRs, I'd just rather not waffle around trying different
programmers, SW packages, etc.  Mainly the lack of details around which
apps and programmers support the 18F series is what struck me as odd.
The parts are not that new, are they?  AVRGCC and avrdude typically have
support for new AVR variants a month or two after Atmel gets them into
production.

Jim

--
Jim Brain, Brain Innovations
snipped-for-privacy@jbrain.com                                http://www.jbrain.com
We've slightly trimmed the long signature. Click to see the full one.
Re: AVR developer needs PIC help



Quoted text here. Click to load it

Not sure whats up with that. You can get the source code, which it says was
done in Borland C V4... Might easily be able to re-compile it handle more.
(But in the Code page under WinPic it has up to FFF0... so it might be able
to handle it(and Data goes to about 1k))

Quoted text here. Click to load it

Well, there is a low voltage programming mode for ICSP and such... I haven't
use it yet but I think you have to atleast program it once in HV mode to set
the LV programming bit... its all in the programming document... goto the
pic your interested in and it will show some docs and one will be about
FLASH programming for it.

Quoted text here. Click to load it


The PIC's are pretty old I think.... There shouldn't be any problem
programming them as they all use the same basic method. Looking at the
programming specs it says

1.0 DEVICE OVERVIEW

This document includes the programming specifications

for the following devices:

. PIC18F2221 . PIC18F4221

. PIC18F2321 . PIC18F4321

. PIC18F2410 . PIC18F4410

. PIC18F2420 . PIC18F4420

. PIC18F2450 . PIC18F4450

. PIC18F2455 . PIC18F4455

. PIC18F2480 . PIC18F4480

. PIC18F2510 . PIC18F4510

. PIC18F2515 . PIC18F4515

. PIC18F2520 . PIC18F4520

. PIC18F2525 . PIC18F4525

. PIC18F2550 . PIC18F4550

. PIC18F2580 . PIC18F4580

. PIC18F2585 . PIC18F4585

. PIC18F2610 . PIC18F4610

. PIC18F2620 . PIC18F4620

. PIC18F2680 . PIC18F4680



Which is quite a wide range.  I Still have not been able to program the
18F4680 and the 18F4431 for some reason. It might be an incompatibility with
WinPic(yet it does list it as a supported device) and I'm fairly confident I
don't have anything wired up wrong so there must be something I'm
missing(but the document applies equally to the 18F2455 as to 18F4680, yet I
can only get it to work with one of them... so maybe it does have something
to do with WinPic).


AFAIK microchip doesn't bring out many new pics very often... they have a
new 16-bit series comming out sometime and I suppose they are finished with
the pic18 series(as far as new designs are concerned)... I could be wrong
though.


Quoted text here. Click to load it

Jon



Re: AVR developer needs PIC help



Quoted text here. Click to load it

I'll take a crack at it.

Quoted text here. Click to load it

While PICs are quirky, they do bring a lot to the table.


Quoted text here. Click to load it

Did you sample them? Microchip has an outstanding sample program.

Quoted text here. Click to load it

That's a good game plan.

Are you planning on working in assembler initially?

Quoted text here. Click to load it

Sounds like a pretty good plan.

Quoted text here. Click to load it

It's a serial port programmer that requires a true serial port to operate
properly. Michael is probably depricating it for that reason.


Quoted text here. Click to load it

Mine are just simple code dumpers. I really prefer bootloaders and the
Trivial programmers are a fast way to get a bootloader dumped. The ICSP
version will do the job you require.

Quoted text here. Click to load it

That's the new model. The expectation is that the programmer is such a
central part of the development process that having a reliable, processor
driven programmer handling everything is the way to go. But the creates
the chicken/egg problem of how to develop a programmer to program the chip
for the programmer.

Quoted text here. Click to load it

I'm not sure there's a single solution there. winpicprog seems to have
wide coverage of programmers and chip families. Microchip has made the process
difficult because they keep rolling out different programming algorithms
instead of just sticking to a single unified model.

Quoted text here. Click to load it

The Pickit 2 fits this bill nicely.

Quoted text here. Click to load it

That's debatable especially now that Microchip is rolling out the pickits.

Quoted text here. Click to load it

It's designed that way.

Quoted text here. Click to load it

Low voltage programming dedicates an I/O pin in the middle of port B for the
low voltage programming signal. Most developers can't stand losing a pin in
the middle of a full sized port.

Quoted text here. Click to load it

Nope. There's everything from homebrew to professional. And developers are
all over the map. One reason I push the Trivial line is that it's deliberately
designed not to put a huge investment on time/resources. Also any parallel
port programming software that can be configured can use it. So you can
spend the 1/2 hour building and testing it and it'll serve your immediate
needs.

Be aware that you need to ground the cable shield through a cap in order to
get long cable operation. The AC termination scheme I set up isn't necessary.

Gotta go,

BAJ

Re: AVR developer needs PIC help


Quoted text here. Click to load it
Assuming I can program one of them... :-)
Quoted text here. Click to load it
I saw that, but assumed it was a hassle, so I just ordered the parts.
If all goes well, I'll sample something later, since you say it's pretty
easy.
Quoted text here. Click to load it
Would rather not :-).  I can do PIC assembly (well, did SX assembly),
but I suck at it.  C is my lang of choice.
Quoted text here. Click to load it
I noticed that.  I've not had any trouble with the simple parallel port
programmers on the AVR line, and I sometimes need to write special
bootloaders that can be used by the item I am hooking the AVR to
(non-standard pin usage, non standard protocols, etc... I know, but when
you're doing an ATMEGA8 MLF and the interface from the PC is via some
INT lines, that's what I have to use to make a bootloader).

I gather from your position that most folks build the simple programmer
as a one time use to program a better programmer?

Quoted text here. Click to load it
Yeah, and I really want a Linux solution, as I am migrating my
development to Linux soon.
Quoted text here. Click to load it
Is there Linux programmer support for it?
Quoted text here. Click to load it
AHHH.  You ought to note that on your page.  That is a very useful piece
of informaiton.
Quoted text here. Click to load it
Can it serve all my needs :-)

If Pickit 2 has Linux support from someone, then I'll grab one.
Otherwise, I'm afraid I'll wait, as I really want to jump full-time to
Linux (for a host of other reasons).

Jim

Site Timeline