{"id":374,"date":"2025-10-25T11:00:23","date_gmt":"2025-10-25T11:00:23","guid":{"rendered":"https:\/\/www.maddox.pro\/?p=374"},"modified":"2025-10-25T11:00:23","modified_gmt":"2025-10-25T11:00:23","slug":"pc6502-progress","status":"publish","type":"post","link":"https:\/\/www.maddox.pro\/?p=374","title":{"rendered":"PC6502 Progress"},"content":{"rendered":"\n<p>In my <a href=\"https:\/\/www.maddox.pro\/?p=368\">previous blog entry<\/a> I posted about the 6502 computer PCB I made, since then a lot of progress has been made. A lot.<\/p>\n\n\n\n<p>Firstly the timing issue has been overcome, the 6502 will now happily run at 14MHz (tested up to 17MHz), the issue was that the way I had implemented the logic in the CPLD for the FT245 serial port was messed up. My partner, Jayne, helped with that and found the issue.<\/p>\n\n\n\n<p>I&#8217;ve also added a whole bunch of different PCBs, so here&#8217;s a couple of pictures;<\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"700\" height=\"1024\" data-id=\"375\" src=\"https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackFront-700x1024.jpeg\" alt=\"\" class=\"wp-image-375\" srcset=\"https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackFront-700x1024.jpeg 700w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackFront-205x300.jpeg 205w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackFront-768x1123.jpeg 768w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackFront-1051x1536.jpeg 1051w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackFront-1401x2048.jpeg 1401w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackFront-1140x1667.jpeg 1140w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackFront-scaled.jpeg 1751w\" sizes=\"auto, (max-width: 700px) 100vw, 700px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"748\" height=\"1024\" data-id=\"376\" src=\"https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackRear-748x1024.jpeg\" alt=\"\" class=\"wp-image-376\" srcset=\"https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackRear-748x1024.jpeg 748w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackRear-219x300.jpeg 219w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackRear-768x1052.jpeg 768w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackRear-1121x1536.jpeg 1121w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackRear-1495x2048.jpeg 1495w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackRear-1140x1561.jpeg 1140w, https:\/\/www.maddox.pro\/wp-content\/uploads\/2025\/10\/PC6502_FullStackRear-scaled.jpeg 1869w\" sizes=\"auto, (max-width: 748px) 100vw, 748px\" \/><\/figure>\n<\/figure>\n\n\n\n<p>So bottom to top;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Power supply PCB &#8211; This gives me up to 15W from USB-PD or if you used an external 9V-36V DC power supply you can have up to 50W (more on why later)<\/li>\n\n\n\n<li>The 6502 CPU Card &#8211; The 6502 (currently running at 10MHz), ROM, RAM and USB C serial port for console<\/li>\n\n\n\n<li>The FM Speec card &#8211; The has an OPL3 FM engine on board (YMF262) and an allophone speech synth chip (SP0256-AL2). <\/li>\n\n\n\n<li>The Storage card &#8211; this gives 8 bit access to Compact flash cards<\/li>\n\n\n\n<li>Dual SPI card &#8211; this is taken from <a href=\"https:\/\/sbc.rictor.org\/65spi2.html\">Dayrl&#8217;s 65SPI2 project<\/a> All I&#8217;ve done is pop two of these on the PCB and add some address decoding.<\/li>\n\n\n\n<li>65C22 VIA card &#8211; a simple 65C22 based VIA card, allowing 2 ports of 8 bit input or output (or any mix). <\/li>\n\n\n\n<li>Apple II slot card &#8211; This provides two apple II style slots (but not all of the power rails, and a different address)<\/li>\n\n\n\n<li>In the top is a a T2A2 transputer adapter card fro, <a href=\"https:\/\/www.geekdot.com\/t2a2-for-everyone\/\">Geekdot.com<\/a> and this is why having higher power is essential. Each TRAM (Transputer module) needs about 800mA, I plan to have 4 TRAMs.<\/li>\n<\/ul>\n\n\n\n<p>Aside from the Apple II slot everything is working a treat.<\/p>\n\n\n\n<p>Here is a demo of the allophone and FM card (it took me ages to get a single tone from the FM engine);<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video controls src=\"https:\/\/files.mastodon.social\/media_attachments\/files\/115\/418\/678\/213\/518\/667\/original\/e5ccc8fcd2c28a27.mp4\"><\/video><\/figure>\n\n\n\n<p>Next steps with this are, a keyboard and keyboard interface (not PS\/2). And a small display so that I can put graphics on. <\/p>\n\n\n\n<p>Then there is a lot of software that needs writing, saving and loading to the CF card (currently raw data block read\/write work), input from the keyboard and of course output to the display.<\/p>\n\n\n\n<p>I am saving space in my memory map for a <a href=\"https:\/\/feertech.com\/microbeast\/videobeast.html\">VideoBeast from Feersom<\/a> which should make this quite a complete system. Then it&#8217;s just writing some apps for it, things to do raytracing, mandlebrot and maybe a few simple games too.<\/p>\n\n\n\n<p>I update my github with progress as things move forward &#8211; <a href=\"https:\/\/github.com\/TechPaula\/PC6502\/\">https:\/\/github.com\/TechPaula\/PC6502\/<\/a><\/p>\n\n\n\n<p>Most of all this has been a really fun project and nice break from synthesizers. A bit like a holiday.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In my previous blog entry I posted about the 6502 computer PCB I made, since then a lot of progress has been made. A lot. Firstly the timing issue has been overcome, the 6502 will now happily run at 14MHz (tested up to 17MHz), the issue was that the way I had implemented the logic in the CPLD for the FT245 serial port was messed up. My partner, Jayne, helped with that and found the issue. I&#8217;ve also added a whole bunch of different PCBs, so here&#8217;s a couple of pictures; So bottom to top; Aside from the Apple II slot everything is working a treat. Here is a demo of the allophone and FM card (it took me ages to get a single tone from the FM engine); Next steps with this are, a keyboard and keyboard interface (not PS\/2). And a small display so that I can put graphics on. Then there is a lot of software that needs writing, saving and loading to the CF card (currently raw data block read\/write work), input from the keyboard and of course output to the display. I am saving space in my memory map for a VideoBeast from Feersom which should make this quite a complete system. Then it&#8217;s just writing some apps for it, things to do raytracing, mandlebrot and maybe a few simple games too. I update my github with progress as things move forward &#8211; https:\/\/github.com\/TechPaula\/PC6502\/ Most of all this has been a really fun project and nice break from synthesizers. A bit like a holiday.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[40],"tags":[54,31],"class_list":["post-374","post","type-post","status-publish","format-standard","hentry","category-retro-computing","tag-pc6502","tag-retro-computer"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.maddox.pro\/index.php?rest_route=\/wp\/v2\/posts\/374","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.maddox.pro\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.maddox.pro\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.maddox.pro\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.maddox.pro\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=374"}],"version-history":[{"count":1,"href":"https:\/\/www.maddox.pro\/index.php?rest_route=\/wp\/v2\/posts\/374\/revisions"}],"predecessor-version":[{"id":377,"href":"https:\/\/www.maddox.pro\/index.php?rest_route=\/wp\/v2\/posts\/374\/revisions\/377"}],"wp:attachment":[{"href":"https:\/\/www.maddox.pro\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=374"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.maddox.pro\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=374"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.maddox.pro\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=374"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}