Zero Length Packet Automatic Issuing Function; Bulk/Interrupt Out Transfer Zero-Length Packet Automatic Issuing Function - Epson S2R72V18 Technical Manual

1.4.7

Zero Length Packet Automatic Issuing Function

Setting the H_CHx{x=a-e}Config_1.AutoZeroLen bit for the OUT transfer channel enables the
function that automatically issues zero-length packets.
Table 1-28 shows the settings for the function that automatically issues zero-length packets.
Table 1-28 Settings for the zero-length packet automatic issuing function
Item
Zero-length packet
automatic issue
1.4.7.1

Bulk/Interrupt OUT Transfer Zero-Length Packet Automatic Issuing Function

Even when the data size transfer set by the H_CHx{x=a-e}TotalSize_HH,HL,LH,LL registers ends
at exactly the Max Packet Size for a channel executing a bulk/interrupt OUT transfer,
H_CHx{x=a-e}Config_0.TranGo is not cleared automatically, and the transfer continues. When this
channel is scheduled once again, the OUT transaction is executed using a zero-length packet. If this
transaction ends normally, H_CHx{x=a-e}Config_0.TranGo is automatically cleared to end the
transfer, and a TotalSizeCmp status notification (H_CHx{x=a-e}IntStat.TotalSizeCmp) is issued to
the firmware.
S2R72V18 Technical Manual (Rev.1.00)
Register/bit
H_CHx{x=a-e}Config_1.AutoZeroLen Enables the zero-length packet automatic
issuing function. This bit is only valid for OUT
transfers.
EPSON
1. Functions
Description
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