11-10-2026, 02:26 PM
(11-10-2026, 02:05 PM)Graham72 Wrote: Viatel is Australia's variant of Prestel/viewdata. Telstar is a modern viewdata server, so its pages are the same format: 40×24 text, ESC-coded colour and attributes, mosaic graphics, double height, flash, and * / # navigation.
The ROM only has to render that stream and send keystrokes, so it doesn't care which host is behind it.
Where they differ
Line speed: real Viatel is 1200/75 (V.23). The Microbee receives at 1200 and sends at 75. Telstar over TCP doesn't care, so the gateway fakes the modem handshake and carrier, and the data arrives as a plain byte stream.
Pacing: TCP can deliver faster than the 1200 baud the ROM expects. If pages garble or drop characters, the gateway needs to throttle to about 120 chars/sec.
Pages and features: Telstar pages are standard Prestel-style frames. Anything beyond that (telesoftware downloads, response frames, newer extensions) may not be handled by the Viatel ROM.
Connection setup: the ROM expects a dial and answer sequence. Telstar just opens a socket, so the gateway has to present "CONNECT" and carrier at the right moment.
On actual hardware speed may be of a real consequence.
Funnily enough, just paged over to the microbee facebook group and someone has build an serial to IP bridge
And then accessed a Telstar instance using the viatel client
Thanks
Tony