it performed all of its computations in decimal, as opposed to its counterparts which operated in binary. (It was never called "System 10", with or without a hyphen, although many countries tried to rename it. In Spain, the complaint was that "System Ten" means "Hold the system!"). Each partition in turn would handle up to 10 I/O devices, depending on the partition type. For devices such as terminals, printers, card readers and punches, a Multi-Terminal IOC (input-output channel) was installed, which ran at about 20 kbit/s. The partition would respond to CPU I/O instructions to retrieve and transfer data in bursts from terminal devices to main memory, there were no small or single character transfers of data to reduce the demand for access to the processor memory. The processor would cycle through each partition in turn, bypassing those that had an I/O instruction in progress, and executing instructions in the others until either a new I/O was posted or 16.7ms (20ms in Europe) had elapsed and a successful branch instruction was encountered. Theoretically it was possible to "hog" the processor if a successful branch or I/O instruction was never encountered. There were several other types of partitions that could be installed, for the retail terminals an MD (multi-data IOC) was used, which could control up to 10 of them. These devices buffered an entire transaction which was sent in a burst as a speed of 1200 bits per second. As all transfers were made directly from the partition into memory, it was only possible to have one active transmission per terminal at a time, which could cause some devices to 'time out' during transmission on a busy system. In addition, three types of serial communications controllers were available, a synchronous communications adapter, which was capable of emulating the IBM 2780 terminal of the day, however in ASCII, not in EBCDIC, and an asynchronous version of the same was also available, but both were limited to line speeds of no more than 2400 bit/s, the maximum dial-up rate of the day. Another serial controller called the Asynchronous Terminal Adapter (ATA), enable a character-oriented terminal to be interconnect, at a maximum speed of 300 bit/s. Strictly speaking, it was not 10K, but 10,000 characters per partition as the System Ten’s memory consisted of 6-bit characters. It took 10 characters to make up one instruction, so each partition was only able to accommodate