> Ah, ok. I think it'll be hard to get each submit faster > than 12ms, but it > may be possible. Isn't it possible to read multiple > bytes at once,
Yes, if device supports this. I hope I'll be able to send/receive 3-4 I2C bytes in one 'transaction'. > or at > the least use asyncSubmit? Async wouldn't reduce the > latency for any > specific submission, but would reduce the overall > latency. Does each I2C > read depend on the last one? If not, use async, at least > for all but the > last read. It's write-read-write-read so it looks like the best you can do here is to do all writes through async and reads through sync cutting time up to a half (if asyncSubmit takes no time). That's not bad. If all of the above will indeed work properly then the app won't suffer from latencies too much. On Fri, 8 Nov 2002 13:21:36 -0500 (EST) Dan Streetman <[EMAIL PROTECTED]> wrote: > > On Fri, 8 Nov 2002, Boris Dainson wrote: > > > > 48ms...? I thought you said 9-12ms per > syncSubmit...? > >> > >> So, I'm confused - does I2C require sending a 1-byte > submission, 20 times? > >> Or do you send a single 20 byte submission, that takes > a full second to > >> finish? And if so, is the USB subsystem causing the > delay, or I2C...? > >> > > > >Right, it 9-12 for syncSubmit(). > > > >To complete an I2C read operation (1 byte of I2C data) > you'll need 4 of such > >syncSubmits or 48ms. Higher level app may need to read > 20 bytes over I2C as > >a full telemetry packet which adds up to 80 synchSubmits > or 960ms. > > Ah, ok. I think it'll be hard to get each submit faster > than 12ms, but it > may be possible. Isn't it possible to read multiple > bytes at once, or at > the least use asyncSubmit? Async wouldn't reduce the > latency for any > specific submission, but would reduce the overall > latency. Does each I2C > read depend on the last one? If not, use async, at least > for all but the > last read. > > -- > Dan Streetman > [EMAIL PROTECTED] > --------------------- > 186,272 miles per second: > It isn't just a good idea, it's the law! > > > > ------------------------------------------------------- > This sf.net email is sponsored by: See the NEW Palm > Tungsten T handheld. Power & Color in a compact size! > http://ads.sourceforge.net/cgi-bin/redirect.pl?palm0001en > _______________________________________________ > javax-usb-devel mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/javax-usb-devel ------------------------------------------------------- This sf.net email is sponsored by: See the NEW Palm Tungsten T handheld. Power & Color in a compact size! http://ads.sourceforge.net/cgi-bin/redirect.pl?palm0001en _______________________________________________ javax-usb-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/javax-usb-devel
