Moderators: Dave Moll, Andrew Davie, Steve Anderson
Steve Anderson wrote:Yes, sometimes there are subtle differences between manufacturers of supposedly the same device, if you can find the datasheet from the manufacturer that makes the chip in your hand, the better. In the vast majority of cases it probably makes no difference, but these pit-falls are there to trip you up. It shouldn't be so, but here we are...
I've not been caught out by this 555 version, but I so rarely use them that's no surprise. The early versions of the 555 used to put a huge but short current pulse (100s of mA) on the supply line, upsetting other logic using the same supply. This was 'designed out' which may explain some of the foibles between examples from different manufacturers and production dates. The difference between a bipolar and CMOS version can also be quite large, yet they are often considered, "just a 555."
Steve A.
Harry Dalek wrote:Steve might have the code for the Pic one post back , i think this chip is programmed.
Steve Anderson wrote:Yes, it will need programming, though I don't think I've published the code anywhere, not as I recall anyway...(see next paragraph)...
You know, I do not remember drawing up that previous diagram! OK, it is definitely me, it's my 'style' and with my name, but I have no recollection of drawing it! Senility, it creeps up on you! I would have to reverse-engineer something I did to understand what's trying to be accomplished! Grey cells atrophying? Quite possibly/probably!
As for the 12F629 I can program a couple for you (and Richard too if he's interested) and send them on, they're as cheap as chips. (The edible variety).
However, without re-visiting Richards channel and finding the correct video, was his frame-rate 12.5 or 15Hz? The only difference would be some of the timing constants in the software...
However I would need to find the prototype and confirm all works as before, I've (probably) still got it here, somewhere! It's also one way to test any chips before I send then on...
Steve A.
Later... I've found the prototype (as in the photo above), it should work, maybe, it's been well over a decade since the last time it was powered-up.....I don't recall how I programmed the micro as there's no programming connector on the prototype, but that's my problem...
Steve Anderson wrote:Found the latest version of the software I did over a decade ago, summary follows...and this is for what is a small micro...
MEMORY USAGE MAP ('X' = Used, '-' = Unused)
0000 : X---X----------- XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX
0040 : XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXX XXXXXXXXXXXXXXX-
2000 : -------X-------- ---------------- ---------------- ----------------
All other memory blocks unused.
Program Memory Words Used: 113
Program Memory Words Free: 1935
Errors : 0
Harry Dalek wrote:Is thats all the code ? not much too it its all over my head i am guess there are more lines to it !
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