{"id":913,"date":"2022-07-20T02:54:20","date_gmt":"2022-07-20T02:54:20","guid":{"rendered":"http:\/\/tlindner.macmess.org\/?p=913"},"modified":"2022-07-31T17:22:21","modified_gmt":"2022-07-31T17:22:21","slug":"vdg-study-july-2022","status":"publish","type":"post","link":"http:\/\/tlindner.macmess.org\/?p=913","title":{"rendered":"VDG study (July 2022)"},"content":{"rendered":"

I was recently informed of some inaccuracies with the various VDG text screens emulated in MAME. I also recently acquired an RGB2HDMI<\/a>. This device is a very configurable retro computer video to HDMI device. One nice feature it has is to write the frame buffer to a PNG file.\nUsing this device I can capture pixel perfect pictures of my CoCos and compare them to what MAME currently produces.<\/p>\n

First, here is the comparison between a real and MAME emulated CoCo 2.<\/h1>\n

\"2<\/a>\nThe stem of the number ‘3’ is too short in MAME.\nThe “E” stem is too short.\nThe “F” stem is too short.<\/p>\n

Next is the CoCo 2B in normal mode.<\/h1>\n

\"2B<\/a>\nOver all the characters need to be pushed one pixel to the right and one pixel up to properly fit in their boxes.\nThe ‘@’ has an extra pixel.\nThe ‘G’ is the wrong shape.\nThe ‘J’ has an extra pixel.\nThe pound sign has extra pixels.\nThe dollar sign has extra pixels.\nThe apostrophe is missing some pixels.\nThe comma is missing some pixels.\nThe period is missing some pixels.\nThe three is missing a pixel on it’s stem.\nThe ‘6’ is the wrong shape.\nThe ‘9’ is the wrong shape.\nThe colon is missing some pixels.\nThe semi-colon is missing some pixels.<\/p>\n

Next is the CoCo 2B in lowercase mode.<\/h1>\n

\"2B<\/a>\nOver all the characters need to be moved one pixel up and to the right. Except the lowercase J. It only needs to be moved one pixel to the right.\nThe lowercase letter g is the wrong shape.\nThe lowercase letter m has an extra pixel.\nThe lowercase letter p is the wrong shape.\nThe lowercase letter q is the wrong shape.\nThe lowercase letter t is the wrong shape.\nThe lowercase letter w is the wrong shape.\nThe lowercase letter y is the wrong shape.\nThe pound sign has extra pixels.\nThe dollar sign has extra pixels.\nThe apostrophe is missing some pixels.\nThe comma is missing some pixels.\nThe period is missing some pixels.\nThe ‘3’ is missing a pixel on it’s stem.\nThe ‘6’ is the wrong shape.\nThe ‘9’ is the wrong shape.\nThe ‘@’ has an extra pixel.\nThe colon is missing some pixels.\nThe semi-colon is missing some pixels.\nThe ‘G’ is the wrong shape.\nThe ‘J’ has an extra pixel.<\/p>\n

Next is the CoCo 3 in normal mode.<\/h1>\n

\"3<\/a>\nOver all, the characters need to be moved a pixel up.\nThe comma also needs to be moved one pixel to the right.\nThe number 9 has an extra pixel.<\/p>\n

Last is the CoCo 3 in lowercase mode.<\/h1>\n

\"3<\/a>\nOver all the characters need to be moved one pixel up.\nThe lowercase letter g is the wrong shape.\nThe lowercase letter i is the wrong shape.\nThe lowercase letter j is the wrong shape.\nThe lowercase letter m has an extra pixel.\nThe lowercase letter p is the wrong shape.\nThe lowercase letter q is the wrong shape.\nThe comma need to be moved to the right one pixel.\nThe numeral 9 has an extra pixel.<\/p>\n

Special thanks to Pedro Pena<\/a> for a screen capture.<\/p>\n

MAME 0.246 is the first version to contain the fixes for the above.<\/p>","protected":false},"excerpt":{"rendered":"

I was recently informed of some inaccuracies with the various VDG text screens emulated in MAME. I also recently acquired an RGB2HDMI. This device is a very configurable retro computer video to HDMI device. One nice feature it has is … Continue reading →<\/span><\/a><\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-913","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=\/wp\/v2\/posts\/913","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=913"}],"version-history":[{"count":24,"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=\/wp\/v2\/posts\/913\/revisions"}],"predecessor-version":[{"id":935,"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=\/wp\/v2\/posts\/913\/revisions\/935"}],"wp:attachment":[{"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=913"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=913"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/tlindner.macmess.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=913"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}