Renesas R5S72641 User Manual

 
Section 26   USB 2.0 Host/Function Module 

Page 1462 of 2108 

 

R01UH0134EJ0400  Rev. 4.00 

 

 Sep 

24, 

2014 

SH7262 Group, SH7264 Group

1, 0 

PID[1:0] 

00 

R/W 

Response PID 

Specifies the response type for the next transaction 
of the pertinent pipe.  

00: NAK response  

01: BUF response (depending on the buffer state) 

10: STALL response 

11: STALL response  

The default setting of these bits is NAK. Modify the 
setting to BUF to use the pertinent pipe for USB 
transfer. Tables 26.12 and 26.13 show the basic 
operation (operation when there are no errors in the 
transmitted and received packets) of this module 
depending on the PID bit setting. 

After modifying the setting of these bits from BUF to 
NAK during USB communication using the pertinent 
pipe, check that PBUSY is 0 to see if USB 
communication using the pertinent pipe has actually 
entered the NAK state. However, if the PID bits have 
been modified to NAK by this module, checking 
PBUSY is not necessary. 

After S-SPLIT is issued (CSSTS = 1) for split 
transaction in the pertinent pipe, the transaction 
continues until C-SPLIT is completed even when the 
PID bits are set to NAK. 

This module modifies the setting of these bits as 
follows. 

  This module sets PID to NAK on recognizing the 

completion of the transfer when the pertinent pipe 

is in the receiving direction and the SHTNAK bit 

for the selected pipe has been set to 1. 

  This module sets PID to STALL (11) on receiving 

the data packet with the payload exceeding the 

maximum packet size of the pertinent pipe. 

  This module sets PID to NAK on detecting a USB 

bus reset when the function controller function is 

selected.