Mainframe computers type of computers uses the 8-bit code called EBCDIC.
Mainframe computers (colloquially referred to as "big iron") are computers used primarily by large organizations for critical applications; bulk data processing, such as census, industry and consumer statistics, enterprise resource planning; and transaction processing.
In computer architecture, 8-bit integers, memory addresses, or other data units are those that are 8 bits (1 octet) wide. Also, 8-bit CPU and ALU architectures are those that are based on registers, address buses, or data buses of that size.