NEC V850ES/Jx3-H, Руководство пользователя

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V850ES/Jx3H – Plug it!
Field Size Description Value
bLength 1 Descriptor size 0x07
bDescriptor 1 Descriptor type 0x05
bEndpointAddress 1 Endpoint address bits:
D7: Direction 0: OUT, 1: IN
D6-D4: Reserved (0)
D4-D0: Endpoint number 0x81
bmAttributes 1 Attribute bits:
D1-D0: Transfer type
0: Control
1: Isochronous
2: Bulk
3: Interrupt
*D5-D2 is used only by isochronous endpoint
D3-D2: Synchronization type
0: No synchronization
1: Asynchronous
2: Adaptive
3: Synchronous
D5-D4: Usage type
0: Data endpoint
1: Feedback endpoint
2: Dependant feedback endpoint
3: (reserved)
0x02
wMaxPacketSize 2 Payload size bits:
D10-D0: Maximum packet size
D12-D11: auditory transaction number per
μ
frame
(only high-speed isochronous and interrupt)
0: No addition (1 transaction /
μ frame)
1: 1 (2 transaction / μ frame)
2: 2 (3 transaction / μ frame)
3: Not in use (reserved)
0x0040
bInterval 1 Polling interval for data transfer endpoint
Full/low speed interrupt: specify with unit of ms
(number of frames)
High-speed isochronous/interrupt: specify N
for 2 raised to the power of N-1
with unit of
μ frame
(for example, 1 polling in 8 μ frames when
bInterval is 4)
Full-speed isochronous: specify N for 2 raised
to the power of N-1
with unit of 1ms
High-speed bulk/control: specify the maximum
NAK rate for endpoint
with unit of
μ frame
0 means that it does not respond NAK on
OUT/DATA transaction
0x00
Table 26: Endpoint Descriptor Serial Conversion Sample
Field Size Description Value
bLength 1 Descriptor size 0x07
bDescriptor 1 Descriptor type 0x05
Language Code: 0x09 0x04 bString 41
Manufacture: “NEC Electronics Co.”
Table 27: String Descriptor Mass Storage Sample
User’s Manual U19647EE2V0UM00
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