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Atari's Plato Cartridge question

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Part of the reason the orange color was chosen should be obvious, but I would also state that output of characters in black was done to help prevent artifact coloring from happening on real crt's at the time, some of which had really horrible dot pitch, the result of which made white hard to read as a foreground color. It was and effective way to keep it legible across all displays.

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First workable graphic display of berzerk game, shown from pterm and Atari.

 

This is looking better than I had hoped! :)

 

-Thom

As I had mentioned the character at term output would look better than the greeked representation in the character editor ;)

http://atariage.com/forums/topic/196354-ataris-plato-cartridge-question/?p=3959606

Edited by _The Doctor__

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Well, it's because I'm using the characters in BOLD mode, which causes each character to be enlarged x 2 (or 4 pixels for every 1 pixel).

 

And yes, for everybody else watching, these are single characters uploaded into the terminal, so it draws very fast.

 

-Thom

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Looks excellent, and given the method used should be decently playable. Hats off to you. I'm thinking you can bold and unbold to show death happening after being hit and what ever character you've created for final death. :)

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Andre LaMothe on the AtariAge Facebook page asked if he could see a demonstration of writing TUTOR code on PLATO...so I made a video:

 

Enjoy,

 

 

-Thom

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I seem to have stumbled upon a stress test for the Atari PLATO terminal. I wrote a quick TUTOR program that draws lines in a moire' pattern across the screen.

 

It works fantastically at 1200 baud.

 

At 2400, it drops lines..looks like it's saturating the buffer. ;)

 

-Thom

Some 3rd party OS's included faster line drawing and fill routines. I wonder if that would marginally improve the draw speeds? Unless everything is done with internal code, especially since it might be drawing on two buffers at once? (Zoomed in and out)

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PDF'ing the MPP-1000E modem manual tonight, I came across these passages:

 

In the introduction:

post-53052-0-50645100-1518510699.jpg

And a Q/A on page 25:

post-53052-0-29156300-1518510705.jpg

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And that's part of the slow down, as it's bit banging the joystick port. There is a good deal of work to do. What was thought to be ingenious at the time or helpful can be a hindrance later. I've long wanted to build a flow control buffer for such modems and convert/put them on the 850, MIO, P:R: connection etc.

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PDF'ing the MPP-1000E modem manual tonight, I came across these passages:

 

 

From what's been disassembled so far:

LB925:
        RString "Microbit 300 baud"
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PDF'ing the MPP-1000E modem manual tonight, I came across these passages:

 

In the introduction:

attachicon.gifintro.jpg

And a Q/A on page 25:

attachicon.gifP25 Q12.jpg

 

While working on the disassembly, I had a hunch that the Microbits code might've been borrowed from MPP. Turns out the source code found between addresses A0AC to A1CF (Pages 7-9) of the Smart Term 4.1 cartridge were nearly copy/pasted into the Learning Phone.

 

https://archive.org/details/MPPSmartTerminalv4.1

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While working on the disassembly, I had a hunch that the Microbits code might've been borrowed from MPP. Turns out the source code found between addresses A0AC to A1CF (Pages 7-9) of the Smart Term 4.1 cartridge were nearly copy/pasted into the Learning Phone.

 

https://archive.org/details/MPPSmartTerminalv4.1

 

Here's a link to the code found in The Learning Phone.

 

https://github.com/michaelsternberg/tlp/blob/50aada8a8fe7c7673f9b7feeb48bbd47c2647d04/tlp.asm#L3587

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Anyone else jumping on? I noticed Brentarian, and tried to term talk him a few times and leave a note, but no dice.

 

-Thom

I have a log on, unfortunately haven't had time to test it yet. I have Monday off, perhaps I'll have some free time.

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It is for the most part what it should be, but there's a bit to go. I'm pretty sure based on how and where the serial code sits the MIO's self inserted serial will not work or black box for that matter... I'll put the rom in an ultimate again, and try each... flow control would be nice in combination with a buffer in the modem(lantronix or otherwise)

Edited by _The Doctor__

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Well, PLATO does do software flow control (there is a sequence called CATCHUP which causes the formatter at PLATO's end to stop sending data until a subsequent CAUGHTUP sequence is received, much like XON/XOFF), this needs proper implementation in the cartridge, as well as a larger input buffer.

 

The disassembly is progressing on github, I already know we can rip the MPP modem code out, so that we can gain some bytes, and we should be able to add a check to see if R is already in HATABS, this could be done if we altered the cartridge to boot the disk first, but it would ultimately mean that we'd either have to do two versions of the cart, with 850 bootstrap support, and without...or something similar.

 

Really need more eyes looking @ the code.

 

-Thom

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on the disassembly front, looks like more of the SIO routines have been documented. Still going. :) I'll be taking another pass at it this evening.

 

-Thom

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on the disassembly front, looks like more of the SIO routines have been documented. Still going. :) I'll be taking another pass at it this evening.

 

Is there a comprehensive PLATO protocol or terminal definition somewhere?

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