IBM System/370 Channel Emulation
Original Publication Date: 1981-May-01
Included in the Prior Art Database: 2005-Feb-11
Some I/O devices, such as the IBM 3203-5 Printer, were designed to attach to the IBM System/370 channel. In order to attach the IBM 3203 5 Printer to systems which do not have the S/370 channel interface, it is either necessary to design such an interface, design a new attachment for the printer, or emulate the System/370 channel interface. The S/370 channel interface was emulated in the IBM System/38 for the purpose of attaching the 3203-5 Printer. The 5/38, for example, has a channel 10 (Fig. 1) and an I/O controller (IOC) 20 which includes a microprocessor. An I/O adapter 30 is attached to IOC 20 and contains the microcode for the microprocessor in IOC 20. Adapter 30 also includes registers and drivers and receivers which are shown in greater detail in Fig. 2.