29.15.47 Otg Device In Endpoint Transmit Fifo Status Register; (Otg_Dtxfstsx) - ST STM32F412 Reference Manual

RM0402
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.

29.15.47 OTG device IN endpoint transmit FIFO status register

(OTG_DTXFSTSx)

Address offset: 0x918 + 0x20 * x, (x = 0 to 5)
Reset value: 0x0000 0200
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
28 27 26 25
Res. Res. Res.
12 11 10 9
r r r r
USB on-the-go full-speed (OTG_FS)
24 23 22
Res. Res. Res.
8 7 6
INEPTFSAV[15:0]
r r r
RM0402 Rev 6
21 20 19 18
Res. Res. Res. Res.
5 4 3 2
r r r r
17 16
Res. Res.
1 0
r r
1053/1163
1122