PIC32MX250F128B and PICKIT4

[Nigel Goodwin]

Has anyone tried programming the PIC32MX250F128B using a PK4? - I'm trying to do so using the terminal circuit at: https://geoffg.net/terminal.html, well actually the updated USB keyboard version at: https://hackaday.io/project/173216-ascii-video-terminal - I had boards made at JLCPCB as usual.

When I try and program it, I just get "Failed to get Device ID. Please make sure the target device is attached and try the operation again.
Connection Failed." - I've tried it on two PK4's, and two computers (one Win7, one Win10), and power from programmer is turned ON.

I did try it using my ZIF socket PicKit adaptor I build - with the same result - although later investigation showed that this 32MX chip doesn't use the same programming pin's as the 16F/18F 28 pin devices. I was also surprised to see that there's three different pairs of pins that can be used for programming this device, and it (supposedly) accepts which ever one you use.

Luckily, I had socketed the chip - and I have a 28 pin PIC Starter board at home (with an on-board programmer), which accepts this same chip, and I was able to program it using that instead of the PK4. I've not had it connected to a screen yet, but my scope shows a perfectly normal looking video waveform coming out of the composite port.

I even tried programming it with a PK3 (again, two different ones, on different computers), but I couldn't get either PK3 to work, they both fail with the message "The programmer could not be started: Could not connect to tool hardware: PICkit3PlatformTool, com.microchip.mplab.mdbcore.PICKit3Tool.PICkit3DbgToolManagerConnection Failed.". Google shows this to be a common issue.

 

[Ian Rogers]

I have bought 40 pic18f46k22 off RS... I now believe half of them are rejects.. All the ones that are faulty have the same batch number... Piggin annoying... Geoff's stuff normally work very well..

I think some chinesium rejected parts have infiltrated normal supply lines..

 

[Nigel Goodwin]

I have bought 40 pic18f46k22 off RS... I now believe half of them are rejects.. All the ones that are faulty have the same batch number... Piggin annoying... Geoff's stuff normally work very well..

They work fine, just not with the PK4

Even the original one I had a few years ago won't work with the PK4, but all program fine in my MicroStick2.

I think the ones I've just bought came from Farnell, as RS was out of stock? - but I could be confused, I've been doing a LOT of switching between them, trying to order parts.

I think some chinesium rejected parts have infiltrated normal supply lines..

Well a LOT of PIC's have been out of stock for extended periods, at everyone who stocks them, including MicroChip Direct - with some projected lead times over a year away.

 

[rjenkinsgb]

I had a problem programming some PICs recently, in a minimal test circuit.

That turned out to be not having enough load on the 5V supply, so it was being pulled up slightly by the programming voltage through the reset resistor!

That was using an ICD4.

 

[Nigel Goodwin]

I had a problem programming some PICs recently, in a minimal test circuit.

That turned out to be not having enough load on the 5V supply, so it was being pulled up slightly by the programming voltage through the reset resistor!

That was using an ICD4.

Well historically, as you probably know, MicroChip always used to specify a diode in series with the reset pull-up resistor - but stopped doing so a considerable time back, and now just specify a 10K resistor.

I don't 'think' that will be the problem, but I'll check it out, just in case. I'll also check to make absolutely sure the pins read to the PK4 as well, just in case the new track is O/C or something stupid like that.

 

[Nigel Goodwin]

Just an update, I've got it connected to a TV set, and the start-up display works fine - not got it connected to a serial port yet.

 

[Nigel Goodwin]

I had a bit of time today, so I thought I'd start populating another couple of boards - and while doing so, check on the ICSP connections.

Rather embarrassingly I'd got the programmer connected the wrong way round

There's a silkscreen pin description on the bottom of the PCB, below the pins rather than next to them, and I presumed the 1-6 were in the same order as the ICSP connection above - but no, they run 6-1 instead (with no numbers).

Flipped the PK4 round, and it programs fine now!.

 

[Ian Rogers]

Flipped the PK4 round, and it programs fine now!.

LOL.... Sounds more like my sort of issues...

I have ordered a pic 32mx170xxxx to make one of those LCD backpacks... I already have a screen.

Lets see how it runs.

 

[be80be]

I had the same thing happen could not for the life of me get it to program with the pickt4
but the MicroStick2. never has a problem programming it.
I have like 3 chips I thought where bad and about 2 years ago I got a MicroStick2 found my old pic32 chips and
they all programmed fine on it.

 

[Nigel Goodwin]

Just a quick update, I've got it connected to a serial port (FTDI board to PC) and a USB keyboard, all is working well. I'm pretty impressed with the Composite video output, nice and clear, nice and stable - I can't try the VGA output yet, as I'm waiting for some VGA sockets from China (the prices from RS or Farnell were crazy).