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NXP Semiconductors
Symbol
Access
Description
For the other endpoints, the toggle can only be reset to zero when the endpoint is reset.
RF/ TV
R/W
Rate feedback mode / toggle value
For bulk endpoints and isochronous endpoints this bit is reserved and must be set to zero.
For the control endpoint zero this bit is used as the toggle value. When the toggle reset bit is set,
the data toggle is updated with the value programmed in this bit.
When the endpoint is used as an interrupt endpoint, it can be set to the following values.
„0‟: Interrupt endpoint in „toggle mode‟
„1‟: Interrupt endpoint in „rate feedback mode‟. This means that the data toggle is fixed to zero for
all data packets.
When the interrupt endpoint is in „rate feedback mode‟, the TR bit must always be set to zero.
T
R/W
Endpoint type
„0‟: Generic endpoint. The endpoint is configured as a bulk or interrupt endpoint
„1‟: Isochronous endpoint
NBytes
R/W
For OUT endpoints this is the number of bytes that can be received in this buffer.
For IN endpoints this is the number of bytes that must be transmitted.
Hardware decrements this value with the packet size every time when a packet is successfully
transferred.
Note: If a short packet is received on an OUT endpoint, the active bit will be cleared and the
NBytes value indicates the remaining buffer space that is not used. Firmware calculates the
received number of bytes by subtracting the remaining NBytes from the programmed value.
Address
Bits 21 down to 6 of the buffer start address.
Offset
This address offset is updated by hardware after each successful reception/transmission of a
packet. Hardware increments the original value with the rounded up integer value when the
packet size is divided by 64.
Note: When receiving a SETUP token for endpoint zero, the hardware will only read the
SETUP bytes buffer address offset to know where it has to store the received SETUP
bytes. Hardware will ignore all other fields. In case the SETUP stage contains more than
8 bytes, it will only write the first 8 bytes to memory. A USB compliant host must never
send more than 8 bytes during the SETUP stage.
UM10858
User manual
COMPANY PUBLIC
All information provided in this document is subject to legal disclaimers.
Rev. 1.4 — 14 May 2018
314514
UM10858
PN7462 family HW user manual
© NXP B.V. 2018. All rights reserved.
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