Welcome to #MOVember, one asm MOV instruction each day.
The Motorola MC68000 has a BEAST of a MOV instruction.
Official assembler mnemonic: MOVE. Refreshingly clear!
You could move to and from registers and/or memory. 8-, 16-, 32- data sizes. Post increment, predecrement. Including memory-to-memory moves (Ferris Bueller soundtrack voice: Oh Yeah).
*d++ = *s++ is a single instruction in 68000.
Officially destination on the right: MOVE A7,D0 copies the A7 register to D0
The beast grows. My #68k computer is getting closer to the finish line. Chewed through a lot this weekend!
Adjusted common ROM address lines, they were going over the chips and it bothered me. Plus, I'll probably be bouncing those in and out for a while until I venture to programming via a boot loader.
Wired up the many buffered address lines. I did a continuity check last night and it looks good so far. :blobsweat:
Finished the control line buffer and distributed the outputs. I used a big fat purple wire for /DTACK out of respect (or disrespect depending on whom you ask) :blobcatangel:
Finished the /IACK decoder
Wired up the GAL inputs and some of the outputs
New TODOs queued up:
Finish connecting the 68681 serial chips
Finish placing decoupling caps
Replace 7404 with open-drain 7405 variant to work properly with the /RESET line
My #68k home brew computer is coming along nicely. I’ve decided on 512Kx16 ROM and 1Mx16 RAM, and just a 68K-era 68C681 serial chip for I/O for now. I might hook up a parallel port and the FPGA VGA interface I’m working on later. I’ve started hooking up the serial chip and preparing placements for bus buffers and transceivers. 555-based power-on reset circuit is set as well.
There is something really calming about carefully measuring and weaving hookups on the #breadboard.
Here's a #68k CPU family portrait: one of the oldest (68000) and one of the youngest (68060). I'm always surprised at how big the “Texas Cockroach” actually feels on one's hand!
Atari ST experts: I’m looking for someone to help me avoid the chore of writing a tool that converts GFA Assembler’s proprietary tokenized format to plain text. Boost’s appreciated. #68K#AtariSThttps://github.com/jhorneman/amberstar/issues/1
More progress on my #68k computer. Buffers are in and placements sorted for the other chips after some scooting. Data lines are hooked up. The ATF22V10 is programmed, a simple joy that was ^^. Thanks for the tip, @gorplop !
The complexity level has reached the scary threshold, so I took some time to put together a schematic, a singular reference instead of my pile of papers... now to get it plotted on an A1 sheet... XD
Just have to say... thanks to all of the #kicad contributors who have made so many improvements over the years. The changes for 7.0 alone are excellent.
"Screen shots" of various games running on my Mac Plus. Though lacking color, the high resolution (for the time) screen of the early Macintosh really put out some impressive graphics, to my eye.
This is my rough roadmap for #Macstodon:
(no guarantees on ANY of it though, depends on how long I keep interest without burning out or getting bored, and what's technically possible with MacPython)
Note: development is very slow at the moment because I am doing a lot of coding at my day job and don't want to also do it in my free time.
1.1
pick what to display in each of the three columns
show lists, hashtags, bookmark feeds
support for viewing polls, MAYBE for creating them
MAYBE filters for notifications?
MAYBE support multiple servers?
MAYBE support calckey?
At that point, I would consider it "feature-complete" and a finished project.
#RetroComputing#VintageMac folks: does anyone have, or know where I can find, drivers for the Mirror Technologies “Tornado Graphics Card”?
I picked this card up from eBay the other day. It’s a 24-bit NuBus graphics card that is a rebadged version of the “MicroConversions 2124NB”. It supposedly offers NuBus acceleration, but requires a driver to operate, which I do not have.
There is a driver for the “MicroConversions 2124NB II” that is archived, but this driver doesn’t work with the Tornado.
The good news is that, even unaccelerated, it offers much faster performance in my IIfx than both my Lapis ProColorServer 8•16 II and my Macintosh Display Card 4•8. Haven’t tested to see if it works with Linux yet, though.
Friends of #68k, I am starting to design #ubttix (unix based 32bits os) first on the pi pico and stm32l4 because thats what I have, but the clear goal is to have this run on 68k. Having two arm targets forces me to design it portable.
I have run into the color #68k Microprocessor User's Manual and the cover is stunning! I've been staring at that crummy black and white facsimile for years.
Finally got some time to start working on my next #RetroComputing project - the Mac SE! My plan of attack is as follows:
Disassemble everything and give it a good cleaning
Recap the analogue board
Replace the squirrel-cage fan with a new fan
Recap the power supply
Recap the logic board
Service the floppy drive to the best of my ability
Install a BlueSCSI!
Credit where credit is due - I’m not doing this alone, I’m doing it under the supervision of my dad who is an experienced electronics engineer and is making sure I don’t do anything really dumb (especially when working around high voltage stuff)
I'm interested in analog/digital electronics, PCB design, retro consoles, homebrew computers, emulators, and anything/everything 6502/816/Z80/68K/MIPS!
I'm currently working on a 68000-based homebrew computer because the 68K just doesn't get enough love <3! Actively re-re-learning Verilog/FPGA for various things related to that project and for future uses.
A huge Yamaha OP_ fan, creating hardware and software around the legendary audio chip, you might see some music recommendations for FM music from time to time!
this is Ryza! she's a PowerBook 180 in fairly good condition and the nicest 68k Mac i own.
this MARCHINTOSH, i'm going to try to upgrade Ryza with a WiFi-capable PiSCSI (fka RaSCSI) so i can test and someday play Atelier Esri, my homebrew Atelier demake.
i'm also going to try out a brand new JCS PowerBook 1xx battery. and while i'm in there, i can at least inventory the capacitors and check the PRAM battery.
unfortunately, like most 180s, her active matrix screen is developing "tunnel vision", slowly fading from the corners inward as long as she's on. (it reverts when she's not, but it can take multiple days, far slower than the fading).
fortunately, Ryza has video output and is capable of driving a VGA monitor or capture box, so i won't need to rely on her screen too much.
Welcome home! Let's get you a nice cozy heatsink and get you settled back in your case. Thanks to Amiga of Rochester for getting everything fixed up! #motorola#retrocomputing#68k#mac68k