STD Bus interface with a Z-80 PIO to control mode switching of two operating systems on Port B. Port A is available from the front panel and has four handshake lines on a ribbon connector. The computer will operate alone, with 2K RAM and 9v with a Sinclair type keyboard. or on the STD bus. Three modes allow the computer to operate alone, isolated from the bus, or on the STD bus, easily expandable with RAM, ROM or special function cards from over 120 STD suppliers. The third mode is a software controlled switching mode between the two separate operating systems, and a second microprocessor on the STD Bus. A Sinclair type keyboard connects to a front panel ribbon connector, or an ASCIl keyboard can be connected via an STD Port Card. A nonmaskable interrupt reset is provided
MECHANICAL FEATURES include, all GOLD plated contacts, occupies 4 STD card slots, and has a new plastic front panel. A new Monitor output gives rock steady display while the RF output is retained. A Z80 PIO provides software control for ON/OFF the STD Bus and an 8 Bit Port is provided on a front ribbon connector, with 4 handshake lines. A keyboard (Sinclair type) can be used on a second front mounted ribbon connector. A Port Rotator re-arranges the Sinclair port assignments so that STD cards requiring consecutive ports can be supported. The computer runs either off the bus on its internal 2K RAM, or on the bus with the 2K duplicated so that there are two sets of system variables. Power is supplied from the STD connector (+ 5v) or from the front panel (+ 9v). TAPE IN/OUT and NMI reset button are on the Front panel.
Software in ROM includes SP BASIC and ASZMIC.
