Looking for better VGA monotyped fonts. I notice other people than IBM sold MS Dos Machines
in the early years.
Wang Professional Computer came with what seems to have been a better video card
than IBM had; monochrome, at an 800x300 pixels or a 80x25 with a 10x12 font.
The same goes for the better $$$ video terminals(monohrome). Can we rebuild the
retro hardware, using todays displays at the orginal frequencies. 800x300@ 60 hz?
Also looking for rom dumps of the MCM6571 and the MCM6576 character generators (8x14).
Did any one use anit-alasing on 8x8 fonts as text display?
Ben.
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The easy answer is; Yes.
We can do it with microcontrollers - and either bit-bang the output at the right frequency or lever their existing on-board VGA or HDMI outputs.
800x300 pixels mono is 30,000 bytes of RAM using packed bits per pixel, even un-packed it’s a somewhat modest 0.25MB (modest by todays standards)
Right now I have a little personal project that’s running ‘baremetal’ on a Raspberry Pi (Pi 1B - the original) and this output display via HDMI is relatively trivial to do.
Making a modern LCD display look like an older CRT is an issue though - it can be overcome in software (e.g. phosphor persistence) and bandwidth limitation which cause an artificial aliasing of the dots if you try hard enough.
My project is using an 8x8 pixel font which happens to match the old Acorn/BBC Micro font, however 8x10 looks a little nicer. Taking it to 10x12 would give much more scope for prettier characters, but that introduces other issues to do with pixel/bit packing into bytes (if one bit per pixel) but nothing a good optimising compiler can’t handle (or hand coded assembler!)
-Gordon
I have FPGA card with VGA out and PS2 keyboard. The problem is I have a 50,27,24 Mhz clock.
The developers seem to want me to use only 640x400 video and run a virtual ARM risc processor.
I want to use it to emulate older big iron, IBM’s , PDP’s UK big iron, but the FPGA software has routing issues with timing. I can’t make changes other than what I have modeled so far, So I can’t impliment a faster dot clock. for say 800x600 vga (40 mhz) even if a PLLcan generate it, cause something may break, thus I need to find older video timing. The VGA /PS2 keyboard are the last
big mods with this retro design from about 1978.
I really wish one could find a display that would run a 400x800 ALTO display format, That was
a nice machne that ran16 bit BCPL.
The PI is a nice machine, but like all computers it is cut to the bare bones for the best profit.
I hope it has all the features, you need for your projects.