V850ES/Jx3H – Plug it!
11.3.5 Processing Flow
Process Description USB Initialization
o
Set NAK for Control Endpoint
A NAK response is sent to all the requests
including automatic execution requests.
It sets for hardware not to return unexpected
data in response to an automatic execution
request until registration of data used for the
automatic execution request is complete.
o
Initialize Request Data Register Area
Descriptor data used to respond to a "Get
Descriptor" request is registered in a register.
Those data include device status, endpoint 0
status, device descriptor, configuration
descriptor, interface descriptor, and endpoint
descriptor.
o
Set Interface and Endpoint
Set the number of supported interfaces, the
status of alternative settings, and the
relationship between the interface and
endpoints.
o
Release NAK for Control Endpoint
The NAK setting at control endpoint is released
during registration of data for an automatic
execution request is complete.
o
Set Interrupt Mask Register
Set the mask for each interrupt source indicated
in the interrupt status register of the USB
function controller.
o
Set D+ Pull-up
Pull-up the D+ signal, and let the host recognize
a device is connected.
Figure 43: Flow Chart Jx3H_PLUGIT_COM application
User’s Manual U19647EE2V0UM00
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