USB Device Controller
1569
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Universal Serial Bus (USB)
29.3.1.6 Receive FIFO Status Register (RXFSTAT)
This read-only register indicates how many bytes are in the receive FIFO for the selected endpoint. A write
to this register has no effect. The USB device controller cannot read this register if the EP_NUM.EP_SEL
bit is not set for the endpoint. No receive FIFO status exists for the setup FIFO, because 8 bytes are
always expected.
Figure 29-33. Receive FIFO Status Register (RXFSTAT) [address = FCF78A0Ah]
15
10
9
8
Reserved
RXF_COUNT
R-0
R-0
7
0
RXF_COUNT
R-0
LEGEND: R = Read only; -
n
= value at reset
Table 29-36. Receive FIFO Status Register (RXFSTAT) Field Descriptions
Bit
Field
Value
Description
15-10
Reserved
0
Reserved
9-0
RXF_COUNT
0-3FFh
The receive FIFO byte count 10-bit field indicates the number of bytes currently in the receive FIFO.
Values after system reset or USB reset is low (all 10 bits).