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CHAPTER 8 USB FUNCTION
119
(6)
Data packet send reservation register (DTXRSV)
This register sets the bank where the data packet to be sent is stored. By setting each flag of this register,
the stored data is sent following normal reception of the IN token packet.
The DTXRSV is set with a 1-bit or 8-bit memory manipulation instruction. When the DTXRSV is used in
combination with the handshake packet send reservation register (HTXRSV) as the 16-bit register
USBCON, the DTXRSV is set with a 16-bit memory manipulation instruction.
RESET input sets the DTXRSV to 00H.
Figure 8-15. Format of Data Packet Send Reservation Register
Symbol
6
7
5
4
3
2
1
0
0
0
0
0
DT11EN DT10EN DT01EN DT00EN
DT11EN
Send reservation flag for send bank 1 (Endpoint1)
0
1
FF15H
Address
DTXRSV
After reset
00H
R/W
R/W
No data are sent.
Stored data is sent when all the following conditions are satisfied in EOP during IN packet reception.
Setting is disabled during control read transmission.
INRX (Internal signal) = 1, ADRRST = 1, END1RX = 1, TBYER = 0, TBITER = 0, CRC5ER = 0
DT10EN
Send reservation flag for send bank 1 (Endpoint0)
0
1
No data are sent.
Stored data is sent when all the following conditions are satisfied in EOP during IN packet reception.
INRX (internal signal) = 1, TIDRST = 1, ADRRST = 1, END0RX = 1, TBYER = 0, TBITER = 0, CRC5ER = 0
DT00EN
Send reservation flag for send buffer 0 (Endpoint0)
0
1
No data are sent.
Stored data is sent when all the following conditions are satisfied in EOP during IN packet reception.
INRX (internal signal) = 1, TIDRST = 1, ADRRST = 1, END0RX = 1, TBYER = 0, TBITER = 0, CRC5ER = 0
DT01EN
Send reservation flag for send buffer 0 (Endpoint1)
0
1
No data are sent.
Stored data is sent when all the following conditions are satisfied in EOP during IN packet reception.
Setting is disabled during control read transmission.
INRX (internal signal) = 1, ADRRST = 1, END1RX = 1, TBYER = 0, TBITER = 0, CRC5ER = 0