Going backwards, can't even get a basic blinky working now

[Demon]

Talk about varying absolute maximum specs from one PIC to another:

16F877
Voltage on VDD with respect to VSS.................+7.5V
Voltage on MCLR with respect to VSS...............+14V

Was plan A, but I'm forgetting about the 16F877; keeping it for disposable pet projects now. I've wasted enough days trying to figure what I'm doing wrong.

18F4550
Voltage on VDD with respect to VSS.................+7.5V
Voltage on MCLR with respect to VSS...............+13.25V

Gotta be prepared to use this series, in case I ever get the C++ USB code figured out.

18F26K22
Voltage on VDD with respect to VSS.................+6.5V
Voltage on MCLR with respect to VSS...............+11V

This is my plan B unless there's something even sweeter out there, has 2 USART circuits. I could use one to talk to the PC via USB, and the other to talk with other PICs. Starting to test these as soon as my ZIFs come in. I'm making my own soldered test boards; not trusting the Lab-X1 with its funky blinking for no apparent reason.


I wish I knew absolute specs varied this much before; I never paid much attention to that. I've already put in a few order to DigiKey, Newark and Mouser for all sorts of odds and ends;including some Zeners.

Robert

"I'm killing the planet single-handedly with shipping."

[tumbleweed]

And then you've got the newer K and Q families...

18F26K40
Voltage on VDD with respect to VSS.................+6.5V
Voltage on MCLR with respect to VSS...............+9V

The 26K22 has been one of my "goto" devices for a long time.

[Demon]

Yeah, I got a bunch of 18F26K22 and 18F46K22 from MicroChipDirect a while ago, as well as a bunch of other ICs (sensors, i/O interfaces, etc).

Has MicroChip come up with a newer better USB series than the 18F2550/18F4550?


EDIT: Yeah, this is an interesting MCU: PIC18F04/05/14/15Q40.

I need to find a smaller package though, something with 3-4 I/O pins that can USART at a good clip. These look interesting (not really interested in the low-voltage line):

16F18015/25/44/45
16F18313/18323

(...runs off to MicroChip Direct to see if they still offer 3-demos to customers...)

Robert

[tumbleweed]

PIC18F04/05/14/15Q40

You won't be programming those with PBP.
If you're sticking with PBP, make sure you pick something that's supported, since a lot of the newer chips aren't (and won't be).

Has MicroChip come up with a newer better USB series than the 18F2550/18F4550?

In the 18F family there's the 18F2xK50/18F4xK50, but that's about it. They're pretty similar to the 4550, just a bit newer.

[Demon]

In the 18F family there's the 18F2xK50/18F4xK50, but that's about it. They're pretty similar to the 4550, just a bit newer.

And 50% cheaper on Digikey in Canada. :O

I guess they're phasing out the older series...?

Robert

[tumbleweed]

Microchip rarely obsoletes a device. You can still get most ancient pics.
What they do is to raise the price, so you're always better off using the newer devices... they'll be cheaper and likely more available.

[Ioannis]

Regarding the zeners, you do not have to worry about that. Programmer takes care of the voltages needed for every chip by its own.

When I said about bias, I meant that you did not left the pin MCLR free in the air (especially if that pin is programmed as a MCLR pin). It should have a resistor of around 10K to the Vdd rail.

Otherwise this could lead to random resets of the PIC.

Ioannis