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Inchworm project started

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Are you using a PC with a true serial port or a USB to RS232 adapter?

You may have a port conflict, make sure you don't have two devices assinged to a single com port. From the hardware manager you can configure the port # and turn the FIFO buffers off.
Don't forget the Inchworm requires a DC power adapter. At least 100ma @ 9 to 15 VDC tip positive.
Device Manager will let you see and change the settings.
  • Select 16F877 from the config menu before selecting the programmer
  • select programmer / icd2
  • select programmer / settings / communications (COM1 or 2 only)
  • select programmer / download OS (it will come up with a file, select it)
  • wait, you should get an busy led flickering
Should now work.

Device Manager should look similar to this.
**broken link removed**

Advanced Settings Tab
**broken link removed**
 
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Sorry to be such a pain in the arse.
it is a true serial port
thank you again 3v0, im reading the rest of that now..
will get back to yall..
i have to test the cable , with sv0's suggestions
i have to test the board , with a scope
i will report the findings in a little bit.

EDIT it has no internal modem
 
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pins 13 & 14 show no oscillator action with the scope
i've attached a photo of the board
 

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between pin 12 and pin 11 shows 5.08V

EDIT::i have to go out for a little bit , back soon
 
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I am thinking you know and did all this but check again.

All the PIC16F877(A) needs to work is
  • the 4 power/gnd, (bypass caps on each pair)
  • a 20MHZ clock source (and caps if crystal)
  • a 10K resistor on pin 1 to pull the (active low) reset high.

pins 12 and 31 are ground
pins 11 and 32 are +5
IIRC the green led works so you can not have them backwards.

If that is all right and if you have the right caps for the osc then you should see the osc osc on the scope. (pins 13,14)

You checked for solder bridges? Esp near the crystal and its caps.

Now check both pins 13 & 14 with the scope.

At this point I would pull the processor and see if I could make it work on a solderless breadboard. But that is me and I do not know if you have a ceramic resonator or crystal with caps.

If it is still flatline you either have a bad chip or it is not programmed.
 
good idea i was thinking the same thing
i'll take the 877 out and breadboard it , i have a ceramic resonator.
 
i had some space on the breadboard.
should it work with a resonator on pin 13 ? if it was programmed to use the crystal?
i dont remember

what i usually do is measure pin 14 on the scope ,with a resonator connected to pin 13, to see if it is running..
 
williB said:
i didnt use a x10 probe , dont have one .

In that case not detecting oscillation isn't very conclusive, you could make a crude x10 probe (as you're not requiring accurate compensation) by simply adding a 9Meg resistor to the end of the probe.

Crystal failure (or the uP not oscillating for some other reason) is a common fault in lots of electronic equipment, one of the first tests is to scope the oscillator pins - but it is essential to use a x10 high impedance probe.
 
Assuming that breadboard layout is what you're measuring?, I find it difficult to even spot a resonator? - and certainly the long wires everywhere, and complete lack of supply decouplers, isn't going to help.
 
Yes you should add the caps.
You also need the 10K pullup on pin 1.

Do not get discouraged, this is good experiance for what you will be doing when you get the programmer working.

The only probe I have is a 10x. I missed that one.

Not sure about how you have the resonator hooked up.
 
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