SH7205 Datasheet, PDF (1307/1904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7200 Series

Section 24 USB 2.0 Host/Function Module (USB)
(1) Pipe Control Register Modifying Procedures
The following bits in the pipe control registers can be modified only when USB communication is
disabled (PID = NAK). Figure 24.8 shows the procedure for rewriting the pipe control registers
from a state in which USB communication is enabled (PID = BUF).
Registers that Should Not be Set when USB Communication is Enabled (PID = BUF):
• Bits in DCPMAXP
• The SQCLR, SQSET, and PINGE bits in DCPCTR
• Bits in PIPECFG, PIPEBUF, PIPEMAXP and PIPEPERI
• The ATREPM, ACLRM, SQCLR and SQSET bits in PIPEnCTR
• Bits in PIPEnTRE and PIPEnTRN
Pipe information modification request
Change PID of the relevant pipe to NAK
Wait until the CSSTS bit
for the pipe becomes 0
When the host controller function is selected.
Wait until the PBUSY bit
for the pipe becomes 0
Start modifying pipe information
Figure 24.8 Procedure for Changing Pipe Information from a USB Communication
Enabled State (PID = BUF)
The following bits in the pipe control registers can be modified only for the pipes that are not
specified in the CURPIPE bits for any of the CPU/DMA0/DMA1-FIFO ports.
Registers that Should Not be Set When CURPIPE for FIFO Port is Set.
• Bits in PIPECFG, PIPEBUF, PIPEMAXP and PIPEPERI
In order to modify pipe information, the CURPIPE bits should be set to the pipes other than the
pipe to be modified. For the DCP, the buffer should be cleared using BCLR after the pipe
information is modified.
Rev. 1.00 Mar. 25, 2008 Page 1275 of 1868
REJ09B0372-0100