PIC16F1454 Connecting To USB Doesn't Work

[rsocor01]

Why Microchip do such stupid things, like two sets of programming pins for low or high voltage?

Oh dear...

Ioannis

It doesn't make any sense to me either.

[rsocor01]

Bad news, I got this response from Melabs.

We tried many years ago, but failed to make the USB commands work in a useful way. In any case there is no further development planned for PBP.

The 18F25K50 is less expensive than the 18F4550, but not as cheap as the 16F1454.

I wonder if they are going to stop selling and supporting PBP after they said "there is no further development planned for PBP". We use their U2 programmers and software a lot. I responded to their email asking if they will keep supporting PBP.

[rsocor01]

The good news is that the 18F25K50 isn't that expensive. I'll order some and I'll give it a try.

[Demon]

I just hit a sweet deal. At that price, I cleaned out everything they had on hand:




These go for $3.91 / 100 at Digikey.

[rsocor01]

I just hit a sweet deal. At that price, I cleaned out everything they had on hand:

Attachment 9860


These go for $3.91 / 100 at Digikey.

Those chips are the cheapest 18F with USB according to the Microchip Advanced Selector Chip tool. I'll order some and give it a try.

[Demon]

Those chips are the cheapest 18F with USB according to the Microchip Advanced Selector Chip tool. I'll order some and give it a try.

Don't bother at Arrow / Verical. I cleaned them out.

[rsocor01]

Don't bother at Arrow / Verical. I cleaned them out.

I bought a few from Mouser. I'm hoping I can make the USB part work without any issues. I'll open a new thread if I have problems.

[Ioannis]

I wonder if they are going to stop selling and supporting PBP after they said "there is no further development planned for PBP". We use their U2 programmers and software a lot. I responded to their email asking if they will keep supporting PBP.

This is not new. For few years now the development of PBP has stopped. Only one man (Charles) supports any bugs found but no further work will be done. I guess he is or will be retired, so no interest by anyone to continue this great compiler.

It is pity that younger software engineers are not interested to take this compiler to the next level, but that is the case.

Ioannis

[tumbleweed]

I don't care much for the 18F1xK50, either of them. They don't have much ram/flash resources, plus...

Why Microchip do such stupid things, like two sets of programming pins for low or high voltage?

That was done for pin-out compatibility with the 18F1xK50, but these things are a royal PITA when it comes to programming them.

The ICSPCLK and ICSPDAT lines are shared with the USB D+/D- pins and that causes all sorts of issues:

- you have to make sure to unplug the USB cable when programming
- you can't program at 5V VDD since the USB D+/D- pins have a max voltage of 3.3V, and the programmers usually use VDD to power the programming pins
The programming spec shows the addtl circuitry required (they used to have a special adapter for this)

The second set of programming pins was added to the 16F part to help overcome this.
The 18F2xK50 is much easier to deal with.

See the PIC16(L)F145X Memory Programming Specification doc DS41620C (the 13/14K50 has similar restrictions)

[Demon]

Thanks for that heads up TW. I would have slapped those "sweet deals" on a breadboard and bricked a few before catching on.
😆

[rsocor01]

That was done for pin-out compatibility with the 18F1xK50, but these things are a royal PITA when it comes to programming

Yes, I agree with you. I had a hard time programming it just to flash an LED. Thank you for the explanation.