USB on-the-go full-speed (OTG_FS)
RM0090
1278/1731
DocID018909 Rev 11
Device mode
OTG_FS Receive FIFO size register (OTG_FS_GRXFSIZ)
Address offset: 0x024
Reset value: 0x0000 0200
The application can program the RAM size that must be allocated to the RxFIFO.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
Reserved
FRMNUM
PKTSTS
DPID
BCNT
EPNUM
r
r
r
r
r
Bits 31:25 Reserved, must be kept at reset value.
Bits 24:21
FRMNUM:
Frame number
This is the least significant 4 bits of the frame number in which the packet is received on the
USB. This field is supported only when isochronous OUT endpoints are supported.
Bits 20:17
PKTSTS:
Packet status
Indicates the status of the received packet
0001: Global OUT NAK (triggers an interrupt)
0010: OUT data packet received
0011: OUT transfer completed (triggers an interrupt)
0100: SETUP transaction completed (triggers an interrupt)
0110: SETUP data packet received
Others: Reserved
Bits 16:15
DPID:
Data PID
Indicates the Data PID of the received OUT data packet
00: DATA0
10: DATA1
01: DATA2
11: MDATA
Bits 14:4
BCNT:
Byte count
Indicates the byte count of the received data packet.
Bits 3:0
EPNUM:
Endpoint number
Indicates the endpoint number to which the current received packet belongs.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
Reserved
RXFD
r/rw
Bits 31:16 Reserved, must be kept at reset value.
Bits 15:0
RXFD:
RxFIFO depth
This value is in terms of 32-bit words.
Minimum value is 16
Maximum value is 256
The power-on reset value of this register is specified as the largest Rx data FIFO depth.