UPSD3422_06 Datasheet, PDF (165/293 Pages) STMicroelectronics – Turbo Plus Series Fast Turbo 8032 MCU with USB and Programmable Logic

uPSD34xx
USB interface
● USB Endpoint Select Register (USEL)
Endpoints share the same XDATA space for FIFOs as well as the same SFR addresses
for Control and FIFO Valid Size registers. The USB Endpoint Select Register (see
Table 82) is used to select the desired direction and endpoint that is accessed when
reading or writing to the FIFO XDATA address space. This register is also used to
select the direction and Endpoint when accessing the USB Endpoint Control Register.
Table 82.
Bit 7
DIR
USB endpoint select register (USEL 0EFh, reset value 00h)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
–
–
–
–
EP[2]
EP[1]
Bit 0
EP[0]
Bit
Symbol
R/W
Definition
FIFO’s Direction Select Bit:
7
DIR
R/W 0: IN FIFO select
1: OUT FIFO select
6
–
–
Reserved
5
–
–
Reserved
4
–
–
Reserved
3
–
–
Reserved
Endpoint Selects Bits:
0: Endpoint0
1: Endpoint1
2:0
EP
R/W
2: Endpoint2
3: Endpoint3
4: Endpoint4
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