chjmartin2 Posted November 27, 2015 Share Posted November 27, 2015 (edited) Hi, I acquired a 64k Coco-2 from a friend, and of course I had to hook it up, and then of course I had to get Drivewire running, and then of course I had to get an FD 500 and an EPROM converter (I also have a Deluxe RS-232 Program pack but have no idea what to do with it), and then of course because I had all of that I had to see Homer Simpson on it. (Every console, computer, etc. that I hook up I have to display homer on it - no clue why that it is, but has been that way a long time.) So I was going to write an image converter that just used text mode but then I found Semigraphics-24 and decided that was the better path. Robert's program relies on a BSAVE of the screen and I still haven't sorted out the proper format. (I will - wish I could have it handed to me on silver platter, but I'll figure out the header and format.) The mode is basically a 32x192 character screen and since you have each of the 8 colors with black as an option in a 4 on and 4 off pattern you get a 64x192 mode but with the requirement that half of the block is black. One interesting way to optimize a picture for this mode is to screen the image with a checkerboard pattern and drive every other pixel to black. Even after error diffusion most of those pixels will stay black. If you use a bayer-type screen with a checkerboard you get a similar effect but lose the benefit of error diffusion - I like the compromise of both. Still have to get it to display on the Coco-2 but I have gotten Robert's editor to work, so just have to figure out format now. POP_SG24.BMPPEYE_SG24.BMPPAPA_SG24.BMPFRED_SG24.BMPMARO_SG24.BMPCHET_SG24.BMPHBIT_SG24.BMPBUGS_SG24.BMPBGS2_SG24.BMP Edited November 27, 2015 by chjmartin2 3 Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted November 27, 2015 Author Share Posted November 27, 2015 Two more... SIMP_SG24.BMP SMAR_SG24.BMP 1 Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted November 28, 2015 Author Share Posted November 28, 2015 Created a different error diffusion method that distributes the error to the new row while choosing the lowest error character slice. I also realized that I am not actually doing this correctly. I am using just the first row of each character rather than the row of the character that corresponds to the row of the character that I am in. I am not sure it matters much as there should be every combination of each of the 8 colors and black even in the first row. Regardless this is what I have at the moment. Satisfied enough to work out the data format. Next thing to show should be a cap from a real Coco-2. 3 Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted November 29, 2015 Author Share Posted November 29, 2015 Anybody happen to know the data transfer rate of the Coco SDC? Not sure if they can still be had but I would really like a better mass storage solution for my Coco-2. 1 Quote Link to comment Share on other sites More sharing options...
Mr SQL Posted November 29, 2015 Share Posted November 29, 2015 Wow this is awesome! I think the extended semigraphics modes were fantastic and made the CoCo better than the CoCo III; IMO they weren't exploited enough bitd. Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted November 30, 2015 Author Share Posted November 30, 2015 I do not want to get ahead of myself but a 60 fps player in this mode would be 6,144 bytes per frame. That is 360 kbytes per second. I have no idea what the transfer rate is for a Coco SDC is. Regardless even at 10 fps or 18 fps this would be awesome. The Tandy Coco-2 comes with a 6 bit DAC built in - so this is a media player waiting to happen. A bank switched ROM would be awesome for this too but that is likely dreaming. I know I cannot do it over the serial cable unless I came up with some amazing compression scheme. I do not even know if the 6809 can move that much data regardless. There is a lot to ponder but again even at 10 fps this mode would be great. Quote Link to comment Share on other sites More sharing options...
MarkO Posted November 30, 2015 Share Posted November 30, 2015 Anybody happen to know the data transfer rate of the Coco SDC? Not sure if they can still be had but I would really like a better mass storage solution for my Coco-2. It has been a few months since I plugged in my CoCo SDC, but I seem to recall it loads fairly quickly.. Talk to Zippster to see about getting a CoCo SDC... MarkO Quote Link to comment Share on other sites More sharing options...
MarkO Posted November 30, 2015 Share Posted November 30, 2015 Anybody happen to know the data transfer rate of the Coco SDC? Not sure if they can still be had but I would really like a better mass storage solution for my Coco-2. If you have some SemiGraphics-24 Images to Load, send me a link and I can place them in an SDC Disk Image and see how fast they load.. MarkO Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted December 25, 2015 Author Share Posted December 25, 2015 I got my Coco-SDC and have been able to use it. Now I have to get these images loaded. I have been distracted by playing games. 1 Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted January 1, 2016 Author Share Posted January 1, 2016 I am very close to getting this right. I am using the MES disk image editing tool and can load graphics into the S24 editor. There is still something wrong as my image is offset by almost 8 characters and some of the characters that I selected don't seem right. I will keep working at it. I'm happy to be this far but a bit lost on what to do next. When I am not so tired tomorrow I will post a picture of what I am getting, maybe somebody else will see what I am missing. I know that I am limiting myself to 128 to 256 for character selection but shouldn't have to - when I don't I get random "0" tops for some reason. Are the text characters missing their normal offsets? Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted January 2, 2016 Author Share Posted January 2, 2016 Ok, so I got an image to show on my Coco but realized that I have some additional debugging ahead of me. I got Xroar running so that will be my emulator for now. I used it to show you what I am getting. So the top is what my encoder thinks it is making. (I don't know why there are little dot artifacts, I have to figure that out too.) The bottom is what I am getting when I load it into Robert's S24 editor. Anyway, something is wrong with my character set and it seems something is wrong with my target palette as well. Chris 1 Quote Link to comment Share on other sites More sharing options...
JamesD Posted January 2, 2016 Share Posted January 2, 2016 It looks like you've made excellent progress. Quote Link to comment Share on other sites More sharing options...
linville Posted January 7, 2016 Share Posted January 7, 2016 I answere your post at www.tandycoco.com/forums -- http://www.tandycoco.com/forum/viewtopic.php?f=49&t=376&p=1471#p1471 Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted January 18, 2016 Author Share Posted January 18, 2016 (edited) Robert helped me and showed me how to fix the header... More is on the way soon! The bright green should be dark green so I have to fix that. Edited January 18, 2016 by chjmartin2 1 Quote Link to comment Share on other sites More sharing options...
chjmartin2 Posted February 9, 2016 Author Share Posted February 9, 2016 Hi All, It has been some time since I have updated this topic. I now have a functional encoder that everyone can use if they would like. Robert's S24 Editor is available here. The zip file containing the encoder and source along with some test images is here: S24Conv.zip Below are pictures taken of a TV using the RF adapter, my bet is that when I get my composite mod in that it will look better. I have to thank both Robert and Simon for their help on this, both gave me great debugging insight and Robert held my hand big time on the header. Regards, Chris 1 Quote Link to comment Share on other sites More sharing options...
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