Data 100


Data 100

Data 100 was a commercial maker of IBM compatible computer peripheral equipment during the 1970s and 1980s. It specialized in remote access workstations with card readers and line printers, compatible with the IBM 2780 and IBM 3780 series. It was purchased by Northern Telecom (which later became Nortel Networks) in 1978.

Peripheral equipment sold and maintained under the Data 100 name: Documation Card Reader (Models 300, 600, and 1200); Paper tape readers; Dataproducts High speed drum printers; Control Data Corporation (CDC) chain train printers; Magnetic Tape drives. Fixed and removable hard disk drives.

One Operating System used in the key-to-disk system, was called FML-11 - which meant Field Modified Level 11. This OS was an interrupt driven, multitasking OS with individual device drivers for the peripheral hardware. The computer hardware did not support stacks, so subroutines were called by executing a "return Jump" RTJ assembler instruction. This instruction modified the code at the beginning of the call function and inserted the return address. Reentrancy was achieved by the use of a double linked list of buffers, which was maintained by the scheduler.

The memory was 64K bytes and in the event of a crash was dumped and analysed in its entirety.

Patching was available with areas of RAM set aside for this purpose.

Communication protocols supported were ASYNC, BISYNC and SNA.