> The way I remember it is that the VT100 comes in several configurations (for > example AVO or > not) and you can field modify it from one to another. > > On the other hand, the VT101 and VT102 are fixed configs (that is, not > intended to be field > upgradable), roughly matching the base and AVO versions of the VT100 in > functionality.
That is basically how I remember it too. The VT100 was terminal that could be field-upgraded, the AVO [1] added, printer port added, graph board (VT105) added, and so on. The VT101 is (officially) a fixed-configuration terminal, similar in features to a 'base' VT100 The VT102 is a fixed-configuration terminal similar in featurers to a VT100 with AVO and printer port (?) Internally the chassis metalwork and PSU are very different between the VT100 and the VT101/VT102 The logic boards are different too, but from what I remember the circuit ideas are much the same, the same 2 custom chips are used in the video circuit of all these terminals. Am I remembering correctly, the VT100 uses an 8080 processor, the VT101 (and VT102 I guess) has an 8085? [1] That acronym is a bit strange for me. Over here, AVO (standing for Amps, Volts, Ohms) is a famous brand of multimeter (analogue and digital) and also other test gear like signal generators and valve testers. It is one of those trademarks like 'Hoover; that has almost become generic, people over here will ask for an 'Avo' meaning a multimeter. -tony
