USB Speed

[Rony]

Hi Darrel, your program is great.
I try it in two ways:

First: i kept the same program in the PIC, (i must send a packet from the PC then the PIC reply), so i run my program and yours since the 2 programs can see the packets together.. anyway the 2 programs wrote the same values, same speed about 340 packets/s.

Second: i changed the PIC program and make it sending packets alone (as you asked) with no delays, just send in a true loop, your program gave me values between 514 and 526 packets/s...

What do you think about it, why i didn't reach 680 packets/s ... i am new with USB, maybe you have better explications... Thank you very much.

Anyway to have better speed which method i must use ( let's say i need about 1000 packets/s), don't worry about the PIC because there is nothing to do it is just a USB to CAN converter, so once the USB packet arrived: the PIC send it throw CAN .....


Thank you again.

[Darrel Taylor]

USB <--> CAN

High speed CAN operates at 1Mbaud, or about 125k bytes/sec. HID will never keep up with that.

I've heard that CDC is faster than HID. But I've yet to try it.

Squibcakes has an example for CDC ...

USB CDC Communications for Dummies!
http://www.picbasic.co.uk/forum/showthread.php?t=5806