| Mus.Cat. NEWUC:20 | Mnfctr: | Date: | Ser. No: - | Model: - |
| Comp: - | Width: mm | Depth: mm | Height: mm | Weight: g |
This is a diagram of the Proposed NUMAC Configuration dated October1974.REB
(NUMAC - Northumbria Universities Multiple Access Computer)
(REB - Initials of author - R.E.Broughton)
On the left is the IBM System 360/67, on the right the IBM System 370/168.
The 360 had two 2860 selector channels and one 2870 Multiplexor channel.
The selector channels connected fast unbuffered, uninterruptible devices
such as disk and drum storage. The multiplexor channel connected slow devices
such as card reader, line printer, console.
The proposed 370 had one 2870 multiplexor, two 2880 block mutiplexor,
and one 2860 selector channels.
Two banks of disks were shared via a two channel switch that enabled
communication between the two computers.
The main memory was just 2MByte at this time because the intention
was to add cheaper OEM memory, but IBM insisted it had to have IBM memory to run its diagnostics.
We did add the OEM memory totalling 8MByte and lived to regret it.
We got very profficient at reading diagnostics and determining which chip was defective.