Data buffer

 

 

 

 

Full

Near Full

Near Empty

Empty

 

 

 

 

 

Remainder

 

256 bytes

 

 

256 bytes

 

 

 

 

 

 

 

 

 

 

 

 

DTR “MARK”

DTR “SPACE”

[Paper out]

When the “paper out’ detector senses the end of the paper, the printer stops printing after printing a maximum of two more lines or on feeding the paper. Immediately after a “paper out” condition is detected, the printer sets to OFF LINE and the DTR changes to “MARK”. (To reset printer after a “paper out’, load paper into the printer and press the ON LINE switch to set the printer to ON LINE.)

[Mechanical error]

Mechanical errors are detected when the front cover is opened during printing, or when the motor locks and the unit will not print. Immediately after a mechanical error occurs, the printer sets the DTR to “MARK” and then sets the printer to OFF LINE. To cancel a mechanical error, close the front cover properly and press the ON LINE switch. If the buzzer sounds and the ALARM lamp flashes at this time, then locate the cause of the error and turn the power for the printer off and back on again to reset the printer.

[Status]

b7

b6

b5

b4

b3

b2

b1

b0

 

Constantly set at “0”

Vertical parity error 1: error

Framing error 1: error

Mechanical error 1: error

Paper empty 1: empty

Buffer empty 1: empty

Buffer overflow 1: overflow

Compulsion switch High level

(Switch is set to ON)

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Page 19
Image 19
Star Micronics SP300 manual DTR Mark DTR Space