How-To Guide

Table Of Contents
R01UH0823EJ0110 Rev.1.10 Page 869 of 1852
Nov 30, 2020
RX23W Group 32. USB 2.0 Host/Function Module (USBc)
32.2.4 CFIFO Port Register (CFIFO),
D0FIFO Port Register (D0FIFO),
D1FIFO Port Register (D1FIFO)
(1) When the MBW bit is 1
(2) When the MBW bit is 0
There are three FIFO ports: CFIFO, D0FIFO, and D1FIFO. Each FIFO port is configured of a port register (CFIFO,
D0FIFO, or D1FIFO) that handles reading of data from the FIFO buffer memory and writing of data to the FIFO buffer
memory, a port select register (CFIFOSEL, D0FIFOSEL, or D1FIFOSEL) that is used to select the pipe assigned to the
FIFO port, and a port control register (CFIFOCTR, D0FIFOCTR, or D1FIFOCTR).
Each FIFO port has the following precautions.
The FIFO buffer for DCP (control transfer) should be accessed through the CFIFO port.
Accessing a FIFO buffer using DMA/DTC transfer should be performed through the D0FIFO or D1FIFO port.
The D0FIFO and D1FIFO ports can also be accessed by the CPU.
When using functions specific to a FIFO port, the pipe number (selected pipe) specified by the CURPIPE[3:0] bits
in the port select register cannot be changed (when the DMA/DTC transfer function is used, etc.).
The same pipe should not be assigned to two or more FIFO ports.
There are two FIFO buffer states: the access right for a FIFO buffer can be on the CPU side or on the Serial
Interface Engine (SIE) side. When the access right for a FIFO buffer is on the SIE side, the FIFO buffer cannot be
accessed from the CPU.
Address(es): USB0.CFIFO 000A 0014h, USB0.D0FIFO 000A 0018h, USB0.D1FIFO 000A 001Ch
b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
Value after reset:
0000000000000000
Bit Symbol Bit Name Description R/W
b15 to b0 FIFO Port This port is used for reading receive data from the FIFO buffer and
writing transmit data to the FIFO buffer.
R/W
Address(es): USB0.CFIFO.L 000A 0014h, USB0.D0FIFO.L 000A 0018h, USB0.D1FIFO.L 000A 001Ch
b7 b6 b5 b4 b3 b2 b1 b0
Value after reset:
00000000
Bit Symbol Bit Name Description R/W
b7 to b0 FIFO Port This port is used for reading receive data from the FIFO buffer and
writing transmit data to the FIFO buffer.
R/W