ICT 1900 was a family of mainframe computers released by International Computers and Tabulators (ICT) and later International Computers Limited (ICL) during the 1960s and 1970s. The 1900 series was notable for being one of the few non-American competitors to the IBM System/360, enjoying significant success in the European and British Commonwealth markets.
| Designer | Ferranti-Packard/ICT/ICL |
|---|---|
| Bits | 24-bit |
| Introduced | 1964 |
| Design | CISC |
| Type | Register–Register Register–Memory Memory–Memory (move) |
| Encoding | Fixed |
| Branching | Comparison, carry, overflow, indexing, counting |
| Page size | 1024 words (1904A/S, 1906A/S, 1903T) |
| Extensions | extended floating point in 1906/7 |
| Registers | |
| General-purpose | 8 24-bit (3 usable for indexing) |
| Floating point | 1 48-bit (96-bit if the extended floating point is present) |