Epson Apex 80 User Manual page 142

Table F-2. Printing enabled/disabled signals and control conditions
On Line
SLCT IN
(Indicator on)
LOW
ON LINE
(S . 2-1/interface)
W
ON LINE HIGH
ON LINE HIGH
HIGH/LOW
OFF LINE
(no effect)
*Even though printing is disabled, data characters are received and acknowledged, since the printer is looking for another DC1 character,
which would allow it to resume printing.
DC1/DC3
ERROR
(Data on/off contr.)
DC1 /DC3
HIGH
(no effect)
DC1 RECV'D HIGH
DC3 RECV'D HIGH
DC1/DC3
LOW
(no effect)
BUSY ACKNLG
HIGH/LOW PULSED EA. CHAR.
HIGH/LOW PULSED EA. CHAR
HIGH/LOW PULSED EA. CHAR.
HIGH NOT GENERATED
Printing
(Disabled/enabled)
ENABLED
(normal cond.)
ENABLED
*DISABLED
DISABLED