GEC 4080

The 4080 is the original 4000 series processor. A 4080 system could support up to 256kb of core store, although this would have been an unthinkable amount when the system was developed - the first one was shipped with 64kb. The system was mostly 16bit, with 32bit and some 64bit instructions. I/O was performed by the BMC, Basic Multiplexor Channel, a second dedicated processor. Up to 3 further I/O processors could be fitted, but for most applications, one was perfectly adiquate.