University Analogue Port

Sinclair User

UNIVERSITY ANALOGUE PORT An analogue port from University Computers is a memory-mapped device and is designed to be used by the ZX-81 Basic instructions PEEK and POKE. It is decoded into 64 locations just below the start of Basic RAM - 15488-15552. The first eight locations are used as an eight-channel analogue input port and digital eight-bit output port. That is an unusual combination and, together with the manual, it can provide a complete demonstration unit for schools. The board is despatched without a box but with an expansion connector at the back for plugging-in the 16K RAM pack. Three LEDs are also provided on the board to test the digital port, as is a light sensor to check the analogue input. There is also an amplifier so that voltages in the millivolt range can be measured. A full circuit diagram is provided and the manual takes you through a very easy course on how to use the port. The same firm can also supply various sensors for heat, light, sound and gas to fit on to the board. It can also supply various relays up to 25 amp 250V for control applications. A very good teaching tool at £39.95 inc. VAT and postage from University Computers, [redacted].

University Computers' analogue port

Sinclair User

VERSATILE BOARD University Computers can now provide a board which plugs into the ZX-81 and not only an analogue port but an EPROM socket and a real-time clock. The port is in two sizes, A and B options. A consists of the analogue port and the EPROM socket. Option B includes the real-time clock as well. A Veroboard experimenters' board is also available from the same company for £7.50, complete with suggested circuits. A free consultancy service is also offered to customers. Option A costs £49.95 and Option B, including batteries. £66.20. An upgrade kit from option A to Option B is available for £30. All prices quoted are for built and tested units. University Computers, [redacted].