General discussions about V-USB, our firmware-only implementation of a low speed USB device on Atmel's AVR microcontrollers
-
guest
Post
by guest » Thu Apr 03, 2008 8:47 pm
How much will the AVR USB load the CPU ?
Is HID or CDC change that load ?
-
christian
- Objective Development
- Posts: 1443
- Joined: Thu Nov 09, 2006 11:46 am
Post
by christian » Thu Apr 10, 2008 12:00 pm
AVR-USB needs the CPU as long as there is USB traffic. This is > 90% os the time if bulk endpoints are involved (as with CDC mode). For all other modes based on control transfers, it depends on how fast you respond to requests. As long as the host polls for a response, there's a lot of USB traffic.