This message is from the T13 list server.
> Why do you think [the host] > need to know the number of bytes to transfer? > That is the device's responsibility, > not the host's. Hmmmm. > [The host] just have > to send the device the CDB, > use the buffer the caller gave you > ... and let the device take it from there. Also the host has to ensure that the device does not move data past the end of the buffer. This is the point Hale always mentions when deprecating AtapiPio host implementations that blindly "phase follow" i.e. always respond to a DRQ INTRQ by moving data precisely as the device requests. No? Scsi says a device that tries to move data past the end of the buffer has provoked a "phase error": in the process of negotiating the count of data bytes moved whichever way, the host wants to end data and proceed to move passed/not status, but the device is still offering more data. Mind you, some hosts have circular buffers i.e. buffers without end. Pat LaVarre Subscribe/Unsubscribe instructions can be found at www.t13.org.
