EP80579 Datasheet, PDF (1042/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
G. SEND_PID_CNT field
H. The number of data bytes indicated in DATA_LEN_CNT from the DATA_BUFFER
I. 16-bit CRC
Note:
A DATA_LEN_CNT value of zero is valid in which case no data bytes would be included
in the packet.
4. After sending the data packet, the controller waits for a handshake response from
the debug device.
• If a handshake is received, the debug port controller:
J. Places the received PID in the RECEIVED_PID_STS field
K. Resets the ERROR_GOOD#_STS bit
L. Sets the DONE_STS bit
• If no handshake PID is received, the debug port controller:
J. Sets the EXCEPTION_STS field to 001b
K. Sets the ERROR_GOOD#_STS bit
L. Sets the DONE_STS bit
26.13.3.3 IN Transactions
An IN transaction receives data from the debug device. It can occur only when the
following are true:
• The debug port is enabled
• The debug software sets the GO_CNT bit
• The WRITE_READ#_CNT bit is reset
The sequence of the transaction is:
1. Software sets the appropriate values in the following bits:
USB_ADDRESS_CNF
USB_ENDPOINT_CNF
TOKEN_PID_CNT[7:0]
DATA_LEN_CNT
WRITE_READ#_CNT(note: this will always be 0 for IN transactions)
GO_CNT (note: this will always be 1 to initiate the transaction)
The debug port controller sends a token packet consisting of:
— SYNC
— TOKEN_PID_CNT field
— USB_ADDRESS_CNT field
— USB_ENDPOINT_CNT field
— 5-bit CRC field.
2. After sending the token packet, the debug port controller waits for a response from
the debug device.
If a response is received:
The received PID is placed into the RECEIVED_PID_STS field
— Any subsequent bytes are placed into the DATA_BUFFER
— The DATA_LEN_CNT field is updated to show the number of bytes that were
received after the PID.
3. If a valid packet was received from the device that was one byte in length
(indicating it was a handshake packet), then the debug port controller:
Intel^® EP80579 Integrated Processor Product Line Datasheet
1042
August 2009
Order Number: 320066-003US