TechHub

EdS@hjalfi posted a nice video (and repo) reverse-engineering a tiny console game thing, which turns out to be 6502 based, with a tiny RAM and small ROM, with lots of paging from a large EEPROM.<a href="https://www.youtube.com/watch?v=jJ0XmZvR4bU" rel="nofollow noopener" translate="no" target="_blank">https://www.youtube.com/watch?v=jJ0XmZvR4bU</a><a href="https://mathstodon.xyz/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> <a href="https://mathstodon.xyz/tags/retroComputing" class="mention hashtag" rel="nofollow noopener" target="_blank">#retroComputing</a>

0x10f<a href="https://digipres.club/@foone" class="u-url mention" rel="nofollow noopener" target="_blank">@foone</a> The instruction set is unorthogonal (which makes programming more fun): - conditional jumps must be program counter relative but unconditional jumps can't be - you can't increment or decrement the accumulator - you can't copy from one index register to another - BIT has no immediate addressing mode - no instruction has all the direct indexed addressing modes (absolute,x, zeroPage,x, absolute,y and zeroPage,y): some have the first three, some have the first two, LDX has the last two, STX has the last one, STY has the second one, CPX and CPY have none - the only indirect addressing modes are the 16-bit indirect, (zeroPage,x) and (zeroPage),y; the first can only be used with JMP and the last two with only a few instructions - no arithmetic shift right (logical only) - no 8-bit rotations (9-bit only) (Someone said the second index register in the 6502 was an afterthought which would make sense.) <a href="https://tech.lgbt/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a>

Jason WeatherlyHrmm, I think I'm going to do a bit of work on the MOS6502 emulator. I still need to implement interrupts and get those ironed out. Not 100% sure how I want to do it, but figure it shouldn't be too horrible. Also, I improved the docs as well because I couldn't remember how to compile the assembly code...lol<a href="https://github.com/JamesTheBard/mos6502" rel="nofollow noopener" translate="no" target="_blank">https://github.com/JamesTheBard/mos6502</a><a href="https://social.linux.pizza/tags/programming" class="mention hashtag" rel="nofollow noopener" target="_blank">#programming</a> <a href="https://social.linux.pizza/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> <a href="https://social.linux.pizza/tags/emulation" class="mention hashtag" rel="nofollow noopener" target="_blank">#emulation</a> <a href="https://social.linux.pizza/tags/python" class="mention hashtag" rel="nofollow noopener" target="_blank">#python</a>

Jason WeatherlyAHAHAHA COME AT ME AI<a href="https://social.linux.pizza/tags/programming" class="mention hashtag" rel="nofollow noopener" target="_blank">#programming</a> <a href="https://social.linux.pizza/tags/python" class="mention hashtag" rel="nofollow noopener" target="_blank">#python</a> <a href="https://social.linux.pizza/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> <a href="https://social.linux.pizza/tags/assembly" class="mention hashtag" rel="nofollow noopener" target="_blank">#assembly</a>

Blake PattersonElements by Desire (Atari Lynx demo) 1080p60<a href="https://www.youtube.com/watch?v=jyhoSRBjHkE" rel="nofollow noopener" translate="no" target="_blank">https://www.youtube.com/watch?v=jyhoSRBjHkE</a><a href="https://oldbytes.space/tags/Atari" class="mention hashtag" rel="nofollow noopener" target="_blank">#Atari</a> <a href="https://oldbytes.space/tags/AtarLynx" class="mention hashtag" rel="nofollow noopener" target="_blank">#AtarLynx</a> <a href="https://oldbytes.space/tags/Lynx" class="mention hashtag" rel="nofollow noopener" target="_blank">#Lynx</a> <a href="https://oldbytes.space/tags/demo" class="mention hashtag" rel="nofollow noopener" target="_blank">#demo</a> <a href="https://oldbytes.space/tags/scenedemo" class="mention hashtag" rel="nofollow noopener" target="_blank">#scenedemo</a> <a href="https://oldbytes.space/tags/demoscene" class="mention hashtag" rel="nofollow noopener" target="_blank">#demoscene</a> <a href="https://oldbytes.space/tags/retrogaming" class="mention hashtag" rel="nofollow noopener" target="_blank">#retrogaming</a> <a href="https://oldbytes.space/tags/retrocomputing" class="mention hashtag" rel="nofollow noopener" target="_blank">#retrocomputing</a> <a href="https://oldbytes.space/tags/vintagecomputing" class="mention hashtag" rel="nofollow noopener" target="_blank">#vintagecomputing</a> <a href="https://oldbytes.space/tags/video" class="mention hashtag" rel="nofollow noopener" target="_blank">#video</a> <a href="https://oldbytes.space/tags/MOS6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#MOS6502</a> <a href="https://oldbytes.space/tags/Epyx" class="mention hashtag" rel="nofollow noopener" target="_blank">#Epyx</a> <a href="https://oldbytes.space/tags/mobilegaming" class="mention hashtag" rel="nofollow noopener" target="_blank">#mobilegaming</a>

Bread80Adding write support to the <a href="https://mstdn.social/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> in the simulator and <a href="https://mstdn.social/tags/CPC_ZERO" class="mention hashtag" rel="nofollow noopener" target="_blank">#CPC_ZERO</a>. The SYS register uses a '174. The clock pulse, to latch the data, could, naively, be driven by a write signal generated by PHI and RWB and gated by ~IO_SEL from the address decoder.But the 6502 de-asserts RWB at the same moment it releases the data bus. Gate delays would mean the clock pulse arriving after the data bus has been released. Bus capacitance could make this work in the real world but I want proper validation. 1/n

MarcThis book has just arrived. Let's see what all the fuss is about and whether the <a href="https://mastodon.xyz/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> or the <a href="https://mastodon.xyz/tags/z80" class="mention hashtag" rel="nofollow noopener" target="_blank">#z80</a> is the better CPU... 😉

Felix Palmen :freebsd: :c64:<a href="https://polymaths.social/@dendrobatus_azureus" class="u-url mention" rel="nofollow noopener" target="_blank">@dendrobatus_azureus</a> <a href="https://polymaths.social/@sotolf" class="u-url mention" rel="nofollow noopener" target="_blank">@sotolf</a> It's <a href="https://mastodon.bsd.cafe/tags/MOS6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#MOS6502</a> assembly, and assuming a <a href="https://mastodon.bsd.cafe/tags/C64" class="mention hashtag" rel="nofollow noopener" target="_blank">#C64</a>, it jumps right in the middle of some hw init routine, writing a CIA register with whatever the accumulator currently holds .... and THEN causes a software interrupt, which was typically only used for patching (non electrically-erasable) ROM?* 🤔 Ok, just in case I miss something obvious: Is this code supposed to make any sense? 😆* could be used for poor-man's syscalls / context switching, but I guess that's not contemporary style 😏

root42Five minutes until we code some <a href="https://chaos.social/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> assembly! Wait... I can't code 6502? Oh, never mind! We'll try anyway!

Bread80Old school DRAMs have a lot of timing requirements. I’ve been validating output from the <a href="https://mstdn.social/tags/CPCZERO" class="mention hashtag" rel="nofollow noopener" target="_blank">#CPCZERO</a> sequencer prototype against them - and everything checks out 🙂Comments in my notes are where the timings depend on other components, such as the multiplexers.<a href="https://mstdn.social/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> <a href="https://mstdn.social/tags/Homebrewcomputer" class="mention hashtag" rel="nofollow noopener" target="_blank">#Homebrewcomputer</a> <a href="https://mstdn.social/tags/amstrad" class="mention hashtag" rel="nofollow noopener" target="_blank">#amstrad</a>

Felix Palmen :freebsd: :c64:I recently took a dive into <a href="https://mastodon.bsd.cafe/tags/C11" class="mention hashtag" rel="nofollow noopener" target="_blank">#C11</a> <a href="https://mastodon.bsd.cafe/tags/atomics" class="mention hashtag" rel="nofollow noopener" target="_blank">#atomics</a> to come up with alternative queue implementations not requiring locking some <a href="https://mastodon.bsd.cafe/tags/mutex" class="mention hashtag" rel="nofollow noopener" target="_blank">#mutex</a>.TBH, I have a hard time understanding the <a href="https://mastodon.bsd.cafe/tags/memory" class="mention hashtag" rel="nofollow noopener" target="_blank">#memory</a> <a href="https://mastodon.bsd.cafe/tags/ordering" class="mention hashtag" rel="nofollow noopener" target="_blank">#ordering</a> constraints defined by C11. I mean, I code <a href="https://mastodon.bsd.cafe/tags/assembler" class="mention hashtag" rel="nofollow noopener" target="_blank">#assembler</a> on a <a href="https://mastodon.bsd.cafe/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> (for the <a href="https://mastodon.bsd.cafe/tags/c64" class="mention hashtag" rel="nofollow noopener" target="_blank">#c64</a>), so caches, pipelines and all that modern crap is kind of alien rocket science anyways 😆.But seriously, they try to abstract from what the hardware provides (different kinds of memory barrier instructions, IMHO somewhat easier to understand), so the compiler can pick the appropriate one depending on the target CPU. But wrapping your head around their definition really hurts the brain 🙈.Yesterday, I found a source telling me that <a href="https://mastodon.bsd.cafe/tags/amd64" class="mention hashtag" rel="nofollow noopener" target="_blank">#amd64</a> (or <a href="https://mastodon.bsd.cafe/tags/x86" class="mention hashtag" rel="nofollow noopener" target="_blank">#x86</a> in general?) always has strong ordering for reads, so no matter which oderding constraint you put in your atomic_load and friends, the compiler will generate the same code and it will work. Oh boy, how should I ever verify my code works on e.g. aarch64 without owning such hardware?

RetroComputingMX¡El MOS Technology KIM-1 (1976) fue la pequeña gran máquina que democratizó la computación! 💻 Basado en el 6502, este kit accesible fue la puerta de entrada para miles de programadores y sentó las bases de la era de las PCs. <a href="https://mastodon.social/tags/retrocomputingmx" class="mention hashtag" rel="nofollow noopener" target="_blank">#retrocomputingmx</a> <a href="https://mastodon.social/tags/Kim1" class="mention hashtag" rel="nofollow noopener" target="_blank">#Kim1</a> <a href="https://mastodon.social/tags/MOS6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#MOS6502</a> <a href="https://mastodon.social/tags/efem%C3%A9ridestecnologica" class="mention hashtag" rel="nofollow noopener" target="_blank">#efeméridestecnologica</a> <a href="https://retrocomputingmx.com/tdxk" rel="nofollow noopener" translate="no" target="_blank">https://retrocomputingmx.com/tdxk</a>

oric_issI've just published the sources for <a href="https://mastodon.social/tags/QR_code" class="mention hashtag" rel="nofollow noopener" target="_blank">#QR_code</a> generator adapted and optimized <a href="https://mastodon.social/tags/Oric" class="mention hashtag" rel="nofollow noopener" target="_blank">#Oric</a>,<a href="https://mastodon.social/tags/MOS6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#MOS6502</a>. Original code by: <a href="https://mastodon.social/@the8bittheory" class="u-url mention" rel="nofollow noopener" target="_blank">@the8bittheory</a>. LINK: 😎<a href="https://github.com/iss000/oricOpenLibrary/tree/main/lib-qrcode" rel="nofollow noopener" translate="no" target="_blank">https://github.com/iss000/oricOpenLibrary/tree/main/lib-qrcode</a>

André FachatWhat started out as a repair video for a broken PET 3032 became a video on repairing two PET keyboards first: <a href="https://youtu.be/bPpjxiyjXZ8" rel="nofollow noopener" translate="no" target="_blank">https://youtu.be/bPpjxiyjXZ8</a> (the rest of the repair is to follow) <a href="https://mastodon.online/tags/8bit" class="mention hashtag" rel="nofollow noopener" target="_blank">#8bit</a> <a href="https://mastodon.online/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> <a href="https://mastodon.online/tags/commodore" class="mention hashtag" rel="nofollow noopener" target="_blank">#commodore</a> <a href="https://mastodon.online/tags/commodorepet" class="mention hashtag" rel="nofollow noopener" target="_blank">#commodorepet</a>

The Oasis BBSIdun-Cartridge Connects C128 to Raspberry Pi <a href="https://techhub.social/tags/Commodore128" class="mention hashtag" rel="tag">#Commodore128</a> <a href="https://techhub.social/tags/C64" class="mention hashtag" rel="tag">#C64</a> <a href="https://techhub.social/tags/RaspberryPi" class="mention hashtag" rel="tag">#RaspberryPi</a> <a href="https://techhub.social/tags/RetroComputing" class="mention hashtag" rel="tag">#RetroComputing</a> <a href="https://techhub.social/tags/IdunCartridge" class="mention hashtag" rel="tag">#IdunCartridge</a> <a href="https://techhub.social/tags/8BitComputing" class="mention hashtag" rel="tag">#8BitComputing</a> <a href="https://techhub.social/tags/MOS6502" class="mention hashtag" rel="tag">#MOS6502</a> <a href="https://techhub.social/tags/C64Development" class="mention hashtag" rel="tag">#C64Development</a> <a href="https://techhub.social/tags/BBS" class="mention hashtag" rel="tag">#BBS</a> <a href="https://techhub.social/tags/SIDMusic" class="mention hashtag" rel="tag">#SIDMusic</a> <a href="https://theoasisbbs.com/idun-cartridge-connects-c128-to-raspberry-pi/?feed_id=3280&_unique_id=68234662b6d62" target="_blank" rel="nofollow noopener" translate="no">https://theoasisbbs.com/idun-cartridge-connects-c128-to-raspberry-pi/?feed_id=3280&_unique_id=68234662b6d62</a>

pagetable6502 Illegal Opcodes in the Siemens PC 100 Assembly Manual (1980) <a href="https://www.pagetable.com/?p=1798" rel="nofollow noopener" translate="no" target="_blank">https://www.pagetable.com/?p=1798</a> <a href="https://mastodon.social/tags/retrocomputing" class="mention hashtag" rel="nofollow noopener" target="_blank">#retrocomputing</a> <a href="https://mastodon.social/tags/aim65" class="mention hashtag" rel="nofollow noopener" target="_blank">#aim65</a> <a href="https://mastodon.social/tags/siemens" class="mention hashtag" rel="nofollow noopener" target="_blank">#siemens</a> <a href="https://mastodon.social/tags/pc100" class="mention hashtag" rel="nofollow noopener" target="_blank">#pc100</a> <a href="https://mastodon.social/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a>

oric_iss<a href="https://mastodon.social/tags/QR_code" class="mention hashtag" rel="nofollow noopener" target="_blank">#QR_code</a> generation on <a href="https://mastodon.social/tags/ORIC" class="mention hashtag" rel="nofollow noopener" target="_blank">#ORIC</a> <a href="https://mastodon.social/tags/MOS6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#MOS6502</a> in just 50 milliseconds (screen drawing included)!😎

Behind The ConsoleVorbereitung für das <a href="https://podcasts.social/tags/VCFe" class="mention hashtag" rel="nofollow noopener" target="_blank">#VCFe</a>. Ein paar Give-aways für die Führung in der <a href="https://podcasts.social/tags/datArena" class="mention hashtag" rel="nofollow noopener" target="_blank">#datArena</a>. <a href="https://podcasts.social/tags/MOS6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#MOS6502</a> <a href="https://podcasts.social/tags/vintagecomputing" class="mention hashtag" rel="nofollow noopener" target="_blank">#vintagecomputing</a> <a href="https://podcasts.social/tags/vclab" class="mention hashtag" rel="nofollow noopener" target="_blank">#vclab</a>

𝚜𝚞𝚣𝚊München? Wenn dir dieses Schild begegnet, fahr nicht einfach vorbei. Da lang geht´s ins Vintage Computer Paradies! VCFe this weekend!Also: abbiegen, Vorfahrt gewähren, und dann straight zurück in die Zukunft, äh, Vergangenheit!<a href="https://mastodon.social/tags/VCFe" class="mention hashtag" rel="nofollow noopener" target="_blank">#VCFe</a> <a href="https://mastodon.social/tags/vcfe24" class="mention hashtag" rel="nofollow noopener" target="_blank">#vcfe24</a> <a href="https://mastodon.social/tags/VintageComputerFestival" class="mention hashtag" rel="nofollow noopener" target="_blank">#VintageComputerFestival</a> <a href="https://mastodon.social/tags/M%C3%BCnchen" class="mention hashtag" rel="nofollow noopener" target="_blank">#München</a> <a href="https://mastodon.social/tags/6502Forever" class="mention hashtag" rel="nofollow noopener" target="_blank">#6502Forever</a> <a href="https://mastodon.social/tags/RetroLove" class="mention hashtag" rel="nofollow noopener" target="_blank">#RetroLove</a> <a href="https://mastodon.social/tags/Commodore64" class="mention hashtag" rel="nofollow noopener" target="_blank">#Commodore64</a> <a href="https://mastodon.social/tags/commodorepet" class="mention hashtag" rel="nofollow noopener" target="_blank">#commodorepet</a> <a href="https://mastodon.social/tags/Amiga" class="mention hashtag" rel="nofollow noopener" target="_blank">#Amiga</a> <a href="https://mastodon.social/tags/atari800" class="mention hashtag" rel="nofollow noopener" target="_blank">#atari800</a> <a href="https://mastodon.social/tags/apple" class="mention hashtag" rel="nofollow noopener" target="_blank">#apple</a> <a href="https://mastodon.social/tags/FloppyPower" class="mention hashtag" rel="nofollow noopener" target="_blank">#FloppyPower</a> <a href="https://mastodon.social/tags/mos6502" class="mention hashtag" rel="nofollow noopener" target="_blank">#mos6502</a> <a href="https://mastodon.social/tags/OldButGold" class="mention hashtag" rel="nofollow noopener" target="_blank">#OldButGold</a> <a href="https://mastodon.social/tags/HackThePast" class="mention hashtag" rel="nofollow noopener" target="_blank">#HackThePast</a> <a href="https://mastodon.social/tags/MuseumZumMitnehmen" class="mention hashtag" rel="nofollow noopener" target="_blank">#MuseumZumMitnehmen</a>

The Oasis BBSBuilding a Commodore 64 from Scratch: No 6510, VIC-II, or SID <a href="https://techhub.social/tags/Commodore64" class="mention hashtag" rel="tag">#Commodore64</a> <a href="https://techhub.social/tags/RetroComputing" class="mention hashtag" rel="tag">#RetroComputing</a> <a href="https://techhub.social/tags/Electronics" class="mention hashtag" rel="tag">#Electronics</a> <a href="https://techhub.social/tags/HomebrewComputer" class="mention hashtag" rel="tag">#HomebrewComputer</a> <a href="https://techhub.social/tags/C64" class="mention hashtag" rel="tag">#C64</a> <a href="https://techhub.social/tags/MOS6502" class="mention hashtag" rel="tag">#MOS6502</a> <a href="https://techhub.social/tags/DIYComputer" class="mention hashtag" rel="tag">#DIYComputer</a> <a href="https://techhub.social/tags/EPROM" class="mention hashtag" rel="tag">#EPROM</a> <a href="https://techhub.social/tags/StaticRAM" class="mention hashtag" rel="tag">#StaticRAM</a> <a href="https://techhub.social/tags/SBC" class="mention hashtag" rel="tag">#SBC</a> <a href="https://theoasisbbs.com/building-a-commodore-64-from-scratch-no-6510-vic-ii-or-sid/?feed_id=3030&_unique_id=680f8105d4f99" target="_blank" rel="nofollow noopener" translate="no">https://theoasisbbs.com/building-a-commodore-64-from-scratch-no-6510-vic-ii-or-sid/?feed_id=3030&_unique_id=680f8105d4f99</a>

Recent searches

Search options

Administered by:

Server stats:

#mos6502