V850ES/Jx3H – Plug it!
Endpoint 0 is the endpoint for control transferring. However, standard device requests,such as the
request used by enumeration for plug-in, are automatically responded by hardware. Therefore, this
should monitor standard requests that are not responded by hardware, class requests, and vendor
requests.
Endpoint 0 Monitoring Process
o
Check CPUDEC Interrupt
If an interrupt is occurred, CPUDEC bit of
UF0IS1 becomes ON (1).
o
Clear Interrupt Flag
Clear the interrupt flag by setting the
CPUDEC bit of UF0IC1 to OFF (0).
o
Load Request Data
Load received data from FIFO, and
structure the request data.
o
Determine Request Type
It distinguishes whether the request is
standard request that is not responded by
hardware automatically, class request, or
vendor request.
o
Process
Request
Process the request depending on the
request type.
Start
CPUDEC
Interrupt?
No
Yes
Process Request
End
Load Request
Data
Determine
Request Type
Clear Interrupt
Flag
Figure 51: Flow Chart Jx3H_PLUGIT_COM
Endpoint 0 Monitoring Process
User’s Manual U19647EE2V0UM00
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