On-Line Printer - RCA 301 Programmer's Reference Manual

ON-LINE PRINTER

Both buffered and unbuffered on-line printers are available in the RCA 301 System. The buffered printers
provide the advantage of off-line scan-print in addition to off-line paper advance, freeing the processor mode on
completion of print table and data line transfer to the buffer. Further, the buffer can be loaded during paper advance
for a prior print instruction.
Two mqdels are available in either the buffered or the unbuffered printers. The important differences between
the two models are (1) the number of characters that can be printed per line, and (2) the number of lines that can
be printed per minute.
One model prints a maximum of 120 characters per line. The printing rate is up to approximately 1000 lines per
minute in the Synchronous Mode which permits the printing of 47 selected characters. The printing rate is up to
approximately 800 lines per minute in the Asynchronous Mode which permits the printing of 64 characters.
The second model prints a maximum of 160 characters per line. The printing rate is up to approximately 1075
lines per minute in the Synchronous Mode and up to approximately 835 lines per minute in the Asynchronous Mode.
The printers can be operated in the following combinations at the indicated speeds:
No. of
Printers
Unbuffered
1 120 Column
160 Column
1
160 Column
1
120 Column #1
2
160 Column #1
2
Buffered
1 120 Column
1 160 Column
2 120 Column #1
160 Column #1
2
(N)-—Normal Mode
(S)—Simultaneous Mode
* Printing at full speed in the Simultaneous Mode is not possible with the 160-column unbuffered printer due to memory interrupt
requirements. If a card read or punch operation is performed in the "S" Mode concurrently with a print instruction in the "N" Mode
the rates are reduced to 715 and 600 lines per minute (1pm) respectively.
The following characteristics are common to both printers:
The Printer is a transistorized device which prepares output documents, printing data directly from the
High Speed Memory of the Computer. Data editing is accomplished in the Computer under the direction of
the stored program. Paper advance is controlled by the Computer program, either directly or through a
paper tape loop in the Printer. Paper advance is independent of the Computer activity at a rate of 150 lines
a second.
Two Computer instructions are directly associated with the On-Line Printer. One controls the On-Line
Printer in the Normal Mode, the other in the Simultaneous Mode. Variations in these basic instructions
permit printing, paper advance for a specified number of lines, vertical tabbing, or page change. Certain
combinations of these functions are also possible with these instructions.
Synchronous Speed
Mortal
moaei
(Ipm) per Printer
1,000
1,075* (N)
#2
#2
1,000
1,075
1,000
#2 1,000
1,075
1,075
#2
(N or S)
715 (N or S)
(N or S)
(N or S)
(N or S)
(N or S)
(N or S)
(N or S)
Asynchronous Speed
(Ipm) per Printer
800 (N or S)
835* (N)
600 (N or S)
800 (N or S)
800 (N or S)
600 (N or S)
600 (N or S)
800 (N or S)
835 (N or S)
800 (N or S)
800 (N or S)
835 (N or S)
835 (N or S)
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