SATO M-8485Se - The Receive Buffer

Section 6. Interface Specifications
The Parallel interface will probably be the most useful in communicating with IBM
PCs and compatibles. The RS232C Serial interface allows connectivity to a number of
other hosts. The USB interface allows the printer to be connected to a computer that
supports peripherals attached to a USB bus. Up to 127 peripherals can be connected
to a sin
g
le USB
p
ort.
WARNING: Never connect or disconnect interface cables (or use a switch box) with
power applied to either the host or the printer. This may cause damage to the
interface circuitr
y
in the
p
rinter/hos
t
an
d
i
s
no
t
covere
d
b
y
warrant
y
.
THE RECEIVE BUFFER
The “Se” printers have the ability to receive a data stream from the host in one of two
ways. The receive buffer may be configured to accept one print job at a time or
multiple print jobs. The single job print buffer is generally used by software programs
that wish to maintain control of the job print queue so that it can move a high priority
job in front of ones of lesser importance. The multiple job buffer, on the other hand
prints all jobs in the order they are received by the printer, and the order of printing
cannot be chan
g
ed.
Sin
g
le Job Buffer
The
p
rinte
r
receives and
p
rints one
j
ob at a time. Each
j
ob must not exceed 2.95 MB.
Multi Job Buffer
The printer is able to continuously receive print jobs, compiling and printing other
jobs at the same time. It acts much like a “print buffer” to maximize the performance
of the host and the
p
rinter.
When using the RS232C Serial interface, the Multi Job Buffer uses either the
Ready/Busy with DTR (pin 20) or X-On/X-Off flow control protocols. See these
sections for more details. With an empty receiving buffer, the status of DTR is “high”
(or an X-On status if using X-On/X-Off ), meaning the printer is ready to receive
data. When the receive buffe
r
is holdin
g
2.0 MB of data
(
1 MB from bein
g
full
),
DTR
Pa
g
e 6-2 SATO “Se” Print En
g
ines