Otg Device In Endpoint Transmit Fifo Status Register (Otg_Dtxfstsx); Endpoint Number) - ST STM32F423 Reference Manual

USB on-the-go full-speed (OTG_FS)
Bits 31:21 Reserved, must be kept at reset value.
Bits 20:19 PKTCNT[1:0]: Packet count
Indicates the total number of USB packets that constitute the transfer size amount of data for
endpoint 0.
This field is decremented every time a packet (maximum size or short packet) is read from
the Tx FIFO.
Bits 18:7 Reserved, must be kept at reset value.
Bits 6:0 XFRSIZ[6:0]: Transfer size
Indicates the transfer size in bytes for endpoint 0. The core interrupts the application only
after it has exhausted the transfer size amount of data. The transfer size can be set to the
maximum packet size of the endpoint, to be interrupted at the end of each packet.
The core decrements this field every time a packet from the external memory is written to
the Tx FIFO.
33.15.44 OTG device IN endpoint transmit FIFO status register
(OTG_DTXFSTSx) (x = 0..5, where
x = endpoint number)
Address offset for IN endpoints: 0x918 + (x * 0x20) This read-only register contains the free
space information for the device IN endpoint Tx FIFO.
31 30 29
Res. Res. Res. Res.
15 14 13
r r r
Bits 31:16 Reserved, must be kept at reset value.
Bits 15:0 INEPTFSAV[15:0]: IN endpoint Tx FIFO space available
Indicates the amount of free space available in the endpoint Tx FIFO.
Values are in terms of 32-bit words:
0x0: Endpoint Tx FIFO is full
0x1: 1 word available
0x2: 2 words available
0xn: n words available
Others: Reserved
1216/1324
28 27 26 25
Res. Res. Res.
12 11 10 9
r r r r
24 23 22
Res. Res. Res.
8 7 6
INEPTFSAV[15:0]
r r r
RM0430 Rev 8
21 20 19 18
Res. Res. Res. Res.
5 4 3 2
r r r r
RM0430
17 16
Res. Res.
1 0
r r