MB86613S Datasheet, PDF (113/134 Pages) Fujitsu Component Limited. – IEEE1394 Open HCI Controller

Preliminary
8.3. Isochronous Transmit
An example of software flowchart for transmitting an isochronous packet is shown in Figure 8.10.
1) Check ITContextControl.active bit and make sure it is cleared.
2) Store the data to transmit in an host memory, except for no data isochronous packet.
3) Store the context program in the host memory. In this case, also set the packet header in the lower 16- bit
field of the first descriptor (i.e., immediate command).
4) Set the transmit start time in the ITContextControl.cycleMatch field (only when ITContextControl.cycle
MatchEnable bit is set).
5) Set the start address of host memory where the context program is stored, in the ITCommandPtr.descrip-
torAddress field. Also set the count; (number of descriptor + 1), since the first descriptor is an immediate
command, in the ITCommandPtr.Z field.
6) Set the ITContextControl.run bit.
7) Wait until the INTA# is set. (when the last descriptor’s ” i ” field contains 11b or 01b and IsoXmitIntMask.i-
soXmitN bit is set.)
8) Check the ITContextControl.eventcode field.
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