Cypress CY7C64113C Manual De Usuario

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CY7C64013C
 CY7C64113C
Document #: 38-08001 Rev. *B
Page 39 of 51
19.0
 USB Mode Tables
Mode
This lists the mnemonic given to the different modes that can be set in the Endpoint Mode Register by writing to the lower nibble
(bits 0..3). The bit settings for different modes are covered in the column marked “Mode Bits”. The Status IN and Status OUT
represent the Status stage in the IN or OUT transfer involving the control endpoint.
Mode Bits
These column lists the encoding for different modes by setting Bits[3..0] of the Endpoint Mode register. This modes represents
how the SIE responds to different tokens sent by the host to an endpoint. For instance, if the mode bits are set to “0001” (NAK
IN/OUT), the SIE will respond with an 
• ACK on receiving a SETUP token from the host
• NAK on receiving an OUT token from the host
• NAK on receiving an IN token from the host
Refer to section 13.0 for more information on the SIE functioning
SETUP, IN and OUT 
These columns shows the SIE’s response to the host on receiving a SETUP, IN and OUT token depending on the mode set in
the Endpoint Mode Register.
A “Check” on the OUT token column, implies that on receiving an OUT token the SIE checks to see whether the OUT packet is
of zero length and has a Data Toggle (DTOG) set to ‘1.’ If the DTOG bit is set and the received OUT Packet has zero length, the
OUT is ACKed to complete the transaction. If either of this condition is not met the SIE will respond with a STALLL or just ignore
the transaction.
A “TX Count” entry in the IN column implies that the SIE transmit the number of bytes specified in the Byte Count (bits 3..0 of the
Endpoint Count Register) to the host in response to the IN token received.
A “TX0 Byte” entry in the IN column implies that the SIE transmit a zero length byte packet in response to the IN token received
from the host.
An “Ignore” in any of the columns means that the device will not send any handshake tokens (no ACK) to the host.
Table 19-1.  USB Register Mode Encoding
Mode
Mode Bits SETUP
IN
OUT
Comments
Disable
0000
ignore
ignore
ignore Ignore all USB traffic to this endpoint
Nak In/Out
0001
accept
NAK
NAK
Forced from Setup on Control endpoint, from modes other than 
0000
Status Out Only
0010
accept
stall
check For Control endpoints
Stall In/Out
0011
accept
stall
stall
For Control endpoints
Ignore In/Out
0100
accept
ignore
ignore For Control endpoints
Isochronous Out
0101
ignore
ignore
always For Isochronous endpoints
Status In Only
0110
accept TX 0 BYte
stall
For Control Endpoints
Isochronous In
0111
ignore
TX Count
ignore For Isochronous endpoints
Nak Out
1000
ignore
ignore
NAK
Is set by SIE on an ACK from mode 1001 (Ack Out)
Ack 
Out(STALL
=0)
Ack 
Out(STALL
=1) 
1001
1001
ignore
ignore
ignore
ignore
ACK 
stall
On issuance of an ACK this mode is changed by SIE to 1000 
(NAK Out)
Nak Out - Status In
1010
accept TX 0 BYte
NAK
Is set by SIE on an ACK from mode 1011 (Ack Out- Status In)
Ack Out - Status In
1011
accept TX 0 BYte
ACK
On issuance of an ACK this mode is changed by SIE to 1010 
(NAK Out - Status In)
Nak In
1100
ignore
NAK
ignore Is set by SIE on an ACK from mode 1101 (Ack In)
Ack 
IN(STALL
=0)
Ack 
IN(STALL
=1) 
1101
1101
ignore
ignore
TX Count
stall
ignore
ignore
On issuance of an ACK this mode is changed by SIE to 1100 
(NAK In)
Nak In - Status Out
1110
accept
NAK
check Is set by SIE on an ACK from mode 1111 (Ack In - Status Out)
Ack In - Status Out
1111
accept
TX Count
check On issuance of an ACK this mode is changed by SIE to 1110 
(NAK In - Status Out)