Hello everybody,

My first post if it works (tried one before but it didn't)
Ok, here we go,
I just got into PICs (with very very limited electronic background tbh, but
I've soldered a LED before so to say) & my programming skills are .. well I
had some basic,pascal,c but so long ago that it is all neglectable.

It took me a while to gather enough info & tools to get started, but now I
have gotten  a few programs running.
Finding its features the most appealing compared to other boards I have been
looking at, I
went for the LAB-X1 experimenter board (PIC16F877-20/P included) together
with
the EPIC programmer. I didn't want to spend much time on putting together
circuits myself to get to learn programming PICs. I also didn't get the
BASIC
compiler though. After a while I think I'll be using some C package (still
have to investigate which) to  program them, but at the moment I'm
experimenting with MPASM, I never looked into assembly language before, but
I find it quite interesting, maybe I'll just stick to it after all.
The hardware seems to work ok, it took me a while to get it running, but now
the included test hexfiles load & execute just fine (it seems to me, anyway)
and -more important- I have gotten a few programs working on it.
But... unfortunately (but to be expected), this success didn't last for
long.

I'm trying to control some LEDs (what else :), with the aid of online
examples, like the ones on piclist (great resource btw)
The 'lite-a-led' eperiment was a great success.
The 'flash-a-led' gave me some problems, I found a 'nested-loop'-delay that
I used but somehow it didn't work right. The LED's either were on or off, no
action at all. It was actually a PIC16F84 example & I thought it might have
something todo with that. I messed a bit with the code without knowing what
I was doing (moved the positions of call delay & clear carry flag around
etc), but didn't get anything to work & so I gave up.
The 'move-a-led' also didnt work properly, it uses a similar delay.
I went looking for other delay methods & I found this great 'delay
generator' on the piclist, so I guess the code just had to be correct.
Meanwhile I got to know MPLAB a bit better & yes, the debugger shows that 1
bit of PORTD 'moves'

The experiment is done on a 10 LED bargraph, but 8 r used. The idea is that
1 lit LED 'moves' from position 1 to 8 & repeats (with RLF PORTD or RRF
PORTD) but, it doesn't do that, I get all kind of strange things, like it
moves 1-4 & then resets. When I fill in other delay times I get different
effects, like a skipping a few positions.
Then I used a 0.25sec generated code & to my amazement it works perfect.

I kept this one & extend the program with a BTFSS instruction on the last
bit of PORTD to make it go down again.
But.... it doesn't, it just toggles between position 1 & 8, other delay
values make it just stick on position 1, or skip a few places on the way
back.
I have replaced the delay code with a NOP &  watched PORTD with the
debugger, it seems to work perfect, 1 bit moves from pos1 to pos8 & back.

So I think I should find the problems somewhere else, but I don't
knowwhereto look.
Possible issues I could think of myself to check:
*All ports are configured as output & set Low, delivered clock is 4MHz
(jumper setting)
*Power supply shud be sufficient (using 2warts, 1 for the expboard
15VDC/500mA & 1 for the programmer12VDC/800mA)
*The programmer stays connected & powered while executing the program on the
expboard, I have tried without it on working & nonworking programs, it never
changed anything.
*the LEDs share the PORTD with the LCD controller, but the documentation
says it is to be ignored.
* Maybe it has something todo with 'jitter', I found some thing on
http://www.piclist.com/techref/microchip/timer.htm
but this gets ways too technical for me.

I would like to ask if there is anybody out there who could point me out wat
todo next? Maybe someppl have similar hardware (&similar problems?)

Further I would like to know, these flashPICs like 877, can they be
reprogrammed a certain limited amount of times, or are they forever
reprogrammable ?

Oh, & did anybody ever order anything from epemag in uk ? I did, I got some
obscure java-order routine inside a webpage.The order was confirmed on the
webpage, but I didn't get any email confirmation, not even after I mailed
them again to ask for it. Epemag doesn't seem very trustworthy to me, are
they to be avoided or has anybody had good experiences with them ?

thanks a bunch in advance & sorry for the long post
best regards

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