SPRT SP-POS8VI User Manual page 13

5 D4
6 D5
7 D6
8 D7
9 D8
10 ACK
11 BUSY
12 PE
13 SEL
17 FG
In
In
In
In
In
Out Answer pulse, LOW level signal indicates
that data have already been received and
the printer gets ready to receive the next
data.
Out HIGH level signal indicates that the
printer is BUSY and can not receive data.
Out HIGH level signal indicates that paper is
end.
Out Pulling up to HIGH level signal by a
resistor
--- Signal Cover