MB86613S Datasheet, PDF (115/134 Pages) Fujitsu Component Limited. – IEEE1394 Open HCI Controller

Preliminary
and ”10000000h” (start address of host memory where the packet data are contained). Since the example
further assumes that another packet is transmitted in the next isochronous cycle, branchAddress contains
”90000000h” which is the start address of host memory where contains a context program to control the pack-
et transmission to be done in the next cycle and Z field contains ”3h” which is the number of descriptor.
The ” i ” field of the OUTPUT_LAST command is being set to ”11b” so that an interrupt event is reported after
completion of isochronous packet transmit.
OUTPUT_MORE
_Immediate
(descriptor- 1)
ITCommandPtr
descriptorAddress=8000000h
Z=3
Context program- 1
cmd
key
b0
=0
=2
reqCount=8
80000000h
skipAddress=8000000h
Z=3
spd 1
dataLength=256
chan
Num
tcode _sy
A
OUTPUT_LAST
(descriptor- 2)
cmd
key
=1
=0
i3 b3
reqCount=256
dataAddress=10000000h
branchAddress=9000000h
Z=3
90000000h
Fig. 8.11 Example of context program Format for isochronous packet Transmit
8.3.2. Descriptor
This section describes the format of descriptor processed by IT- CPC. The descriptor(s) that IT- CPC handles
are OUTPUT_MORE command, OUTPUT_LAST command, OUTPUT_MORE_Immediate command, OUT-
PUT_LAST_Immediate command, and STORE_VALUE command. If the first descriptor is OUTPUT_LAST
command and the reqCount field contains ”0”, no packet is transmitted and one cycle is skipped. So, when
there is a need that does not want to transmit a packet in certain isochronous cycle, use OUTPUT_LAST com-
mand having the reqCount=0. Also, for Immediate command, specify the packet header to the lower 16- byte
field.
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