USB Registers
1756
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Universal Serial Bus (USB) Controller
Table 27-59. USBRXCSRHn Register Field Descriptions (OTG A / Host) (continued)
Bit
Field
Type
Reset
Description
2
DTWE
R
0x0
Data Toggle Write Enable.
This bit is automatically cleared once the new value is written.
0x0 = The DT bit cannot be written.
0x1 = Enables the current state of the receive endpoint data to be
written (see DT bit).
1
DT
R
0x0
Data Toggle.
When read, this bit indicates the current state of the receive data
toggle.
If DTWE is High, this bit may be written with the required setting of
the data toggle.
If DTWE is Low, any value written to this bit is ignored.
Care should be taken when writing to this bit as it should only be
changed to RESET the receive endpoint.
0
RESERVED
R
0x0
Figure 27-55. USBRXCSRHn Register (OTG B / Device)
7
6
5
4
3
2
1
0
AUTOCL
ISO
DMAEN
DISNYET/PIDE
RR
DMAMOD
RESERVED
INCOMPRX
R/W-0x0
R/W-0x0
R/W-0x0
R/W-0x0
R/W-0x0
R-0x0
R/W0C-0x0
Table 27-60. USBRXCSRHn Register Field Descriptions (OTG B / Device)
Bit
Field
Type
Reset
Description
7
AUTOCL
R/W
0x0
Auto Clear.
0x0 = No effect.
0x1 = Enables the RXRDY bit to be automatically cleared when a
packet of USBRXMAXPn bytes has been unloaded from the receive
FIFO. When packets of less than the maximum packet size are
unloaded, RXRDY must be cleared manually. Care must be taken
when using USB DMA to unload the receive FIFO as data is read
from the receive FIFO in 4 byte chunks regardless of the value of the
MAXLOAD field in the USBRXMAXPn register, see.
6
ISO
R/W
0x0
Isochronous Transfers.
0x0 = Enables the receive endpoint for isochronous transfers.
0x1 = Enables the receive endpoint for bulk/interrupt transfers.
5
DMAEN
R/W
0x0
DMA Request Enable.
0x0 = Disables the USB DMA request for the receive endpoint.
0x1 = Enables the USB DMA request for the receive endpoint.
4
DISNYET/PIDERR
R/W
0x0
Disable NYET / PID Error.
0x0 = No effect.
0x1 = For bulk or interrupt transactions: Disables the sending of
NYET handshakes. When this bit is set, all successfully received
packets are acknowledged, including at the point at which the FIFO
becomes full.
For isochronous transactions: Indicates a PID error in the received
packet.
3
DMAMOD
R/W
0x0
DMA Request Mode.
This bit must not be cleared either before or in the same cycle as the
above DMAEN bit is cleared.
0x0 = An interrupt is generated after every USB DMA packet
transfer.
0x1 = An interrupt is generated only after the entire USB DMA
transfer is complete.
2-1
RESERVED
R
0x0