IBM 1132
Encyclopedia
The IBM 1132 Line Printer
was the normal printer for the IBM 1130
computer system. It printed 120 character lines at 80 lines per minute. The character set consisted of numbers, upper-case letters and some special characters.
The 1132 was built around a stripped down IBM 407
printing mechanism. The 407 was IBM's top-of-the-line accounting machine
from the 1950s. The 1130 had 120 power transistor
s, each wired to the print wheel solenoid for a printer column. As the set of 120 print wheels spun, the 1130 received an interrupt
as each of the possible 48 characters moved into position. The printing driver
software had to quickly output a 120 bit vector designating which transistors were to fire to press the print wheel against the ribbon and paper. This put a big performance burden on the CPU, but resulted in an inexpensive (for the time) printer.
Sometimes a printer output line transistor would fail, resulting in a blank print position. If you knew your way around inside the 1130, it was possible to swap circuit cards so as to move the bad print position to near the right end of the printed line. This kept the 1130 usable until the repair person showed up.
The 1132 came in two models with the following characteristics:
Line printer
The line printer is a form of high speed impact printer in which one line of type is printed at a time. They are mostly associated with the early days of computing, but the technology is still in use...
was the normal printer for the IBM 1130
IBM 1130
The IBM 1130 Computing System was introduced in 1965. It was IBM's least-expensive computer to date, and was aimed at price-sensitive, computing-intensive technical markets like education and engineering. It succeeded the IBM 1620 in that market segment. The IBM 1800 was a process control variant...
computer system. It printed 120 character lines at 80 lines per minute. The character set consisted of numbers, upper-case letters and some special characters.
The 1132 was built around a stripped down IBM 407
IBM 407
The IBM 407 Accounting Machine, introduced in 1949, was one of a long line of IBM tabulating machines dating back to the days of Herman Hollerith. It was the central component of any unit record equipment shop. In the late 1950s, the 407 was adapted as an input/output device on early computers,...
printing mechanism. The 407 was IBM's top-of-the-line accounting machine
Unit record equipment
Before the advent of electronic computers, data processing was performed using electromechanical devices called unit record equipment, electric accounting machines or tabulating machines. Unit record machines were as ubiquitous in industry and government in the first half of the twentieth century...
from the 1950s. The 1130 had 120 power transistor
Transistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...
s, each wired to the print wheel solenoid for a printer column. As the set of 120 print wheels spun, the 1130 received an interrupt
Interrupt
In computing, an interrupt is an asynchronous signal indicating the need for attention or a synchronous event in software indicating the need for a change in execution....
as each of the possible 48 characters moved into position. The printing driver
Device driver
In computing, a device driver or software driver is a computer program allowing higher-level computer programs to interact with a hardware device....
software had to quickly output a 120 bit vector designating which transistors were to fire to press the print wheel against the ribbon and paper. This put a big performance burden on the CPU, but resulted in an inexpensive (for the time) printer.
Sometimes a printer output line transistor would fail, resulting in a blank print position. If you knew your way around inside the 1130, it was possible to swap circuit cards so as to move the bad print position to near the right end of the printed line. This kept the 1130 usable until the repair person showed up.
The 1132 came in two models with the following characteristics:
- Standard 48-character-set typewheels include FORTRAN special character set.
- Model 1 prints up to 80 alphameric or 110 numeric lines per minute and can be attached to 1131 CPU Models 1, 2, 3, and 5.
- Model 2 prints up to 40 alphameric or 55 numeric lines per minute and may be attached only to the 1131 CPU Model 4.
- Standard 120 print-line positions spaced 10 characters per inch.
- Operator selection of vertical line spacing, 6 or 8 lines per inch.
- Forms skipping under program control through automatic, paper-tape-controlled carriageCarriage control tapeA carriage control tape was a loop of punched tape that was used to synchronize rapid vertical page movement in most IBM line printers from unit record days through the 1970s. The tape loop was as long as the length of a single page. A pin wheel moved the tape accurately using holes in the center...
. - Printer operation under stored-program control through automatic interrupt system.
- Direct connection to the 1131 Central Processing Unit by means of the 1132 Printer Attachment and an Expansion Adapter.