Epson TM-U590 Technical Reference Manual page 40

Commands for bit image
Select bit-image mode
Define downloaded bit image
Print downloaded bit image
Commands for status
Enable/disable Automatic Status Back (ASB)
Transmit status
Transmit real-time status
Commands for mechanical control
Return carriage to home position
Commands for sub-functions
Initialize printer
Transmit printer ID
Set horizontal and vertical motion units
Select peripheral device
Generate pulse to drawer
Generate pulse to drawer in real-time
Clear buffer(s)
Send real-time request to printer
Select page mode
Select standard mode
Execute test print
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