Thanks Alan, I am very thankful for your patient responses. Regards, Mukund Jampala
>-----Original Message----- >From: Alan Stern [mailto:[EMAIL PROTECTED] >Sent: Wednesday, March 01, 2006 8:45 PM >To: Mukund JB. >Cc: [EMAIL PROTECTED]; Randy.Dunlap >Subject: RE: [linux-usb-devel] RE: Analyze the USB Control transfer limits >Table please.. > >On Wed, 1 Mar 2006, Mukund JB. wrote: > >> >In other words, since low-speed USB runs at 1.5 Mb/s, that's 1500000 >> bits >> >per second, or 1500 bits per frame, or 187.5 bytes per frame. Since >> you >> >can't transfer half a byte, the number is rounded down to 187. >> >> I agree for low speed devices, the max allowable bandwidth for all low >> speed device put together is 1.5Mb/s. >> >> Please see last row of the table below: >> >> 8 24000 30% 3 19 24 --> last but one row >> >> As you said, for 8 bytes payload the max transfer possible are 3 and so >> maximum bytes/Frame are (3*8) = 24 bytes. >> In a similar way what are the values "payload" and "max transfers" to >> get the bytes/Frame as 187. >> >> Max 187500 187 --> last row >> >> Hope I am clear. > >There are no "payload" and "max transfers" values for the last line. >That's why it's formatted differently from the rest of the table. The >last line does not refer to control transfers; instead it talks about the >theoretical maximum capacity of the bus. > >If it helps you to understand the table better, pretend the last line >isn't there at all. > >Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid0944&bid$1720&dat1642 _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
