PDIUSBD12 Datasheet, PDF (10/35 Pages) NXP Semiconductors – USB interface device with parallel bus

Philips Semiconductors
PDIUSBD12
USB interface device with parallel bus
9. Main endpoint
The main endpoint (endpoint number 2) is the primary endpoint for sinking or
sourcing relatively large amounts of data. It implements the following features to ease
this task:
• Double buffering. This allows parallel operation between USB access and local
CPU access thus increasing throughput. Buffer switching is handled automatically.
This results in transparent buffer operation.
• DMA (Direct Memory Access) operation. This can be interleaved with normal I/O
operation to other endpoints.
• Automatic pointer handling during DMA operation. No local CPU intervention is
necessary when ‘crossing’ the buffer boundary.
• Configurable endpoint for either isochronous transfer or non-isochronous (bulk and
interrupt) transfer.
10. Command summary
Table 4: Command summary
Name
Destination
Initialization commands
Set Address/Enable
Device
Set Endpoint Enable
Device
Set mode
Device
Set DMA
Device
Data flow commands
Read Interrupt Register
Device
Select Endpoint
Control OUT
Control IN
Endpoint 1 OUT
Endpoint 1 IN
Endpoint 2 OUT
Endpoint 2 IN
Read Last Transaction Status Control OUT
Control IN
Endpoint 1 OUT
Endpoint 1 IN
Endpoint 2 OUT
Endpoint 2 IN
Read Buffer
Selected Endpoint
Write Buffer
Selected Endpoint
Code (Hex) Transaction
D0
Write 1 byte
D8
Write 1 byte
F3
Write 2 bytes
FB
Write/Read 1 byte
F4
Read 2 bytes
00
Read 1 byte (optional)
01
Read 1 byte (optional)
02
Read 1 byte (optional)
03
Read 1 byte (optional)
04
Read 1 byte (optional)
05
Read 1 byte (optional)
40
Read 1 byte
41
Read 1 byte
42
Read 1 byte
43
Read 1 byte
44
Read 1 byte
45
Read 1 byte
F0
Read n bytes
F0
Write n bytes
9397 750 09238
Product data
Rev. 08 — 20 December 2001
© Koninklijke Philips Electronics N.V. 2001. All rights reserved.
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