Joe, just waiting on a part to arrive.. out of VGA connectors. Will be sending out the next raft of units shortly.
On Fri, Oct 16, 2020 at 12:31 PM Stephen Adolph <twospru...@gmail.com> wrote: > Jim, > yah, I think we will find things that can be improved. for a next board > spin (I only ordered 30 boards initially) I can add a track/ jumper. > nice idea to "power" the DB25 port also! > > The issue of how the fonts look is a bit beyond my pay grade for now. > What is implemented is exactly what was done in the original design. > The version of the design available on Tindie > https://www.tindie.com/products/petrohi/geoffs-vt100-terminal-kit/ > has improved firmware, but I haven't made that M100 friendly. > > The font has grown on me ;) > > > > On Fri, Oct 16, 2020 at 12:09 PM Joe Grubbs <jsgru...@hotmail.com> wrote: > >> Awesome Jim! I can't wait until mine gets here >> >> ------------------------------ >> *From:* M100 <m100-boun...@lists.bitchin100.com> on behalf of Jim >> Anderson <jim.ander...@kpu.ca> >> *Sent:* Friday, October 16, 2020 12:00 PM >> *To:* m...@bitchin100.com <m...@bitchin100.com> >> *Subject:* [M100] having fun with MVT100 >> >> On a more uplifting note, I received my MVT100 in the mail last week and >> I've been having a blast with it! I thought I'd share a few things which >> others might find helpful: >> >> I added the jumper for the BCR TTL serial hack to the machine I've been >> using for my REXCPM (the old SOD hack, because I'm unlikely to go the Z80 >> route and didn't want to be bothered patching things). While I was in >> there I also ran a jumper to supply VDD (which I picked off from a nearby >> via which supplies pin 9 in the BCR port) to pin 22 on the RS-232 port - >> this is the Ring Indicate signal from a modem and isn't connected to >> anything in the M100, but more importantly, it maps to pin 9 when you use a >> DE-9 adapter. I was inspired by Stephen's post about adding a jumper to >> the MVT100 to power it off pin 9 (which I have also done) and which >> reminded me that my old Bluetooth serial adapter also is capable of drawing >> power from pin 9. This way, I can run the MVT100 off either the BCR or the >> RS-232 port and it'll receive power. >> >> If there's a future need to revise the MVT100 board design, it might be >> useful to add a trace and a jumper to allow the user to easily >> enable/disable power draw from pin 9 - the way it is now, I'm not sure >> whether Bad Things would happen if I tried using the board as a USB serial >> adapter while it was connected to my M100, since that would common the >> M100's VDD with the USB power supplied by the PC... >> >> A note on screen resolutions: I had not even thought about this until I >> got it and started playing around with it, but the text font the MVT100 >> uses can look absolutely hideous when it's being scaled poorly by an LCD >> monitor. This isn't specifically an MVT100 issue - LCD monitors often >> wreak havoc on text when they are scaling from a non-native resolution, and >> it's something I'd just forgotten about because it's been so long since I >> had to drive an LCD at its non-native resolution. My original plan for my >> MVT100 was to use it with an older NEC 15" LCD I had which is native >> 1024x768 - too low to be useful for a PC, but I thought the compact size >> and 4:3 aspect ratio would make it a perfect terminal display. Alas, it's >> actually almost the worst thing to use, because the MVT100 output is >> 640x480 and that means there aren't enough pixels to do an acceptable job >> of scaling, giving characters that alternate from skinny to fat as you read >> down a line of text... >> >> I also tried with a 1280x1024 LCD on the theory that I might be able to >> tweak the pixel clock settings in the monitor and get it to map at least >> the horizontal pixels 2:1 but this monitor doesn't let you tweak very much >> (it mostly relies on the auto-adjust routine). I got it looking better >> than the small LCD but I still wasn't very happy with it (and it still >> didn't look as good as sending it into a bit 1920x1080 LCD). >> >> Of course, it looks the best by a long shot when you send it into a good >> old VGA CRT, which arguably is the most retro-looking solution of all, and >> lucky for me I never did throw away that little paper-white monochrome VGA >> monitor I got back in the 90s (yes, I said monochrome VGA!). It's kind of >> perfect for this - it doesn't even pretend to represent all colours, it >> only uses the green signal (which is all the MVT100 is jumpered to output >> as I received it) so it all works out almost as if it was meant to! >> >> One other thing: I don't know what is limiting the display output speed, >> but when I started using the BCR at 57600bps I was expecting the display to >> update faster and it seems like it actually is the exact same speed as it >> was on the serial port at 19200bps. From past experience using dumb >> terminals I had been feeling like even the 19200 output was displaying a >> bit slower than it could (it felt like 9600) and I'm wondering if this is >> just a result of the processor having to take turns between executing >> program instructions and bit-banging each output byte. Please don't take >> this as a complaint about it being slow - the speed is fully in keeping >> with my expectations for the platform, and it's lightning-fast compared >> with the internal LCD :) I just wonder what is limiting it because I know >> the M100 is capable of faster data transfer... (speaking of which, I'm >> still dying to have access to the high-speed large-packet data transfer >> capability for backing up and restoring REXCPM) >> >> Anyway, it all works great and I couldn't be happier with this solution! >> Many thanks to Stephen for sharing your genius ideas with us! >> >> >> >> >> >> >> >> jim >> >>
