The basics of USB-PIC

[Tinkerer]

Carl,
good price. Yes definitely I would want one.
Tinkerer

[Qiaozhi]

I drew up a PIC USB circuit, decided to go back to the 18F4550 since it has more pins in a smaller package. I'll just need to get a socket to do the initial bootloader programming.

Anyway, my thought is to build up some boards with programmed PICs, and send one to each Design Group member. You guys interested?

Hi Carl,

I must have missed this post. Of course, I am interested.

[Carl-NC]

Any chance of using Visual Basic? (Ducks)

*gasp* *heave* Visual WHAT???

Heh, just kidding, I use VB myself for some tasks. For firmware programming, there is no Visual Basic, but there are Basic compilers available for PIC. However, the USB functions would have to be rewritten, and I would avoid that at all costs. For firmware, C is definitely the best choice.

On the software side, the USB library is in a DLL with a C header file, so it might be possible to pull this into a VB program. But I've written in Visual Basic as well as Visual C/C++/C#, and there just isn't much difference between the two. Yes, C language syntax takes getting used to, but if you're going to use C for firmware, then you will be learning C-syntax anyway. Beyond the syntax, which isn't hard, Visual C in no more difficult than VB.

- Carl

[KingJL]

This still an option?

I drew up a PIC USB circuit, decided to go back to the 18F4550 since it has more pins in a smaller package. I'll just need to get a socket to do the initial bootloader programming.

Anyway, my thought is to build up some boards with programmed PICs, and send one to each Design Group member. You guys interested?

I'm late to the scene, but yes I am interested if that is still an option.

[Carl-NC]

I need to get on this. Also looking at making a DDS sweep generator with USB control.

[ivconic]

Can you do extra thing here? Can you present sweep generator in analogue technique? And of course the other, you mentioned.
Simply i can not follow you with advanced technology here. Not your fault, but my.
Regards

[Carl-NC]

Despite an overwhelmingly busy schedule, I have finally managed to get the PCB laid out for the USB interface. I have to travel this coming week, but will try to get some boards made when I get back.

- Carl

[ivconic]

Cheers!

http://rapidshare.com/files/13381713...by_Example.zip


password: groovy

[KingJL]

USB Micro Resources

Carl,
What resources (interrupts, timers, peripherals) does the USB boot/loader code that is in your design use? I am trying to decide on how to provide the rest of the KingFisher PI interface signals. It would be advantageous to know what is available for use, so that I do not have to redesign the code. Mainly I need to generate audio and 600 Hz-2.5KHz filter control frequency. I am thinking of using TIMER0 and TIMER3.

Regards,
J. L. King

[Carl-NC]

You can use whatever the 4550 has available. The bootloader is only used to load the main code, the main code is where everything happens, and you write it as you would normally.

I'm trying to get back to the USB board to finish it. I have one prototype built, I just need to do some testing on it. Been sidetracked on PI and other projects.

- Carl

[KingJL]

.... Been sidetracked on PI and other projects.

Been there...doin' that! Every once in a while I have to let things sit for a day or two before I am enthused again about getting back to them.

[Tinkerer]

USB board

Carl,

I have bought a PICDEM USB DEMO BOARD from MICROCHIP. It comes with the PIC18F4550, so I can start experimenting.

So please scratch my order.

Tinkerer

[Carl-NC]

Sorry for the delay, just been too busy to get it finished.

[Tinkerer]

USB boards

Sorry for the delay, just been too busy to get it finished.

We understand

Tinkerer