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1.4.3.3
Interrupt OUT Transaction
The transfer type (H_CHx{x=b-e}Config_1.TranType) is set to "Interrupt," and the transaction type
(H_CHx{x=b-e}Config_1.TID) is set to "OUT" for the CHx{x=b-e} basic setting register. The
token-issuing interval (H_CHx{x=b-e}Interval_H,L), other basic settings, and then transfer
execution (H_CHx{x=b-e}Config_0.TranGo) are set appropriately, subjecting the channel to
hardware-based USB transfer scheduling. The token-issuing interval (H_CHx{x=b-e}Interval_H,L),
valid FIFO data quantity, and remaining frame time are determined when scheduling selects the
corresponding channels, and an interrupt OUT transaction is executed.
The data packet length of the individual data packets is the smaller of
H_CHx{x=b-e}MaxPacketSize_H,L and H_CHx{x=b-e}TotalSize_HH,HL,LH,LL.
An ACK status notification (H_CHx{x=b-e}IntStat.TranACK bit) is issued to the firmware on
receiving ACK for the interrupt OUT transaction. The FIFO is then updated, freeing the area by
treating the data sent as already sent.
If a NAK is received for the interrupt OUT transaction, the FIFO is not updated, and the area is not
freed. Selecting the corresponding channel again executes the same transaction.
If STALL is received for the interrupt OUT transaction, H_CHx{x=b-e}Config_0.TranGo is
automatically cleared, ending the transfer, and the condition code (H_CHx{x=b-e}ConditionCode)
is set to "STALL." A ChangeCondition status notification
(H_CHx{x=b-e}IntStat.ChangeCondition bit) is then issued to the firmware. The FIFO is not
updated, and the area is not freed.
If a normal response is not received for the interrupt OUT transaction, the FIFO is not updated, and
the area is not freed. The condition code (H_CHx{x=b-e}ConditionCode) is set to "RetryError,"
and a TranErr status notification (H_CHx{x=b-e}IntStat.TranErr bit) is issued to the firmware.
Although Retry processing is performed, H_CHx{x=b-e}Control.TranGo is automatically cleared
to end the transfer if three successive errors occur, and then a ChangeCondition status notification
(H_CHx{x=b-e}IntStat.ChangeCondition bit) is issued to the firmware.
S2R72V18 Technical Manual (Rev.1.00)
EPSON
1. Functions
59
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