The IBM System/32 or IBM 5320, was introduced in january 1975 and was a midrange computer with a built-in display screen, disc drives, a printer, and database report software. The main focus for this computer was small to midsize businesses for accounting applications. The main programming language for the System/32 was RPG II.

The System/32 was a single-user 16-bit computer. It was the successor to the System/3 model 6, and the first system to incorporate hardware and a comprehensive software bundle. It was described in the press as a compact computer for first-time users with little or no computer programming experience. The System/32 quickly surpassed the system/3 as most installed IBM computer. The system was leased for around $1000/month.

The computer resembles a large office desk with a very small six-line by 40 character display. Because of the design, the computer was nicknamed the Bionic Desk. A line-printer was built in, and faced the operator who sat in front of the computer. The operator could print reports, memos, billing statements, address labels and more. The machine was completely source code compatible with its successor the System/34, so upgrading was a matter of recompiling the software.

System Architecture

The system/32 featured a 16-bit processor known as the Control Storage Processor. Where the System/3 had a hardwired processor, the System/32 had the instruction set implemented in microcode. It used a vertical microcode format, with each microinstruction occupying 16 bits of control storage. There were 19 different microinstruction opcodes, that could carry out different operations depending on which bits were set in the rest of the microinstruction. This method resulted in 70 distinct microinstructions in total. There was an optional set of scientific macroinstructions which implemented support for floating point arithmetic in microcode. This enabled higher languages such as a Fortran Compiler.

Memory and Storage

The System/32 could be configured with 16,24, or 32 kilobytes of main memory, and 4 to 8 kilobytes of control storage. The larger control storage was needed to support the scientific instruction set. The system provided a single hard-drive in either 5, 9, or 13MByte. It also included an eight" floppy drive that could read floppies from the IBM 3740 family. The floppy disks were single sided, and contained 77 tracks. Each track held 26 128-byte sectors. Later IBM offered an extended format that had 512 byte sector, quadrupling the storage capacity of the disk.