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These are great videos. George is so cool at this stuff. Im building it along with him and want to see a series on writing to the floppy.

What really surprises me is that the control signals are so basic and low level, and then the data is literally just a single pin in and out. So out of 36 conductors, only one carries your actual data. That's crazy.

EEEEEEEEEEEEEEEEEEEEEEEEEEEE prom

Extremely useful!

Cool.

BTW you can use CA2/CB2 as an additional output bit, by setting the specified bits in the Peripheral Control Register. Alternatively you can hook up the LCD directly to the CPUs databus including the R/W input. However you would need to decode part of the address space for the enable pin.

At 10:15 you wonder why the motor is like it is. It's not (just) so it can fit, but because maintaining constant angular velocity is critical for correct operation, and for that, increasing the moment of inertia is very useful, so anything that perturbs the speed of the disk has to do more work to achieve it. By spreading out the motor like that, it can use its own mass as a flywheel.

Debug why

Awesome and love the methodical explanation

I think you could fit everything on a single breadboard if you squeze a bit the TTL chips, i see a lot of space trough them!

Very cool indeed!

Can you please list all the components you used

Great

The 2 notches are strain relief so the disk does not bend at the window

Hi, are you planning to finnish the floppy controler by adding it's ability to write to floppy's?

What would hapen if you use UART to store data, instead of FM or MFM? That way you can use a simple microcontroller to read and write.

Busco como conectar floppy drive 3" interno A externo vía puerto paralelo, like the backpack cdrom parallel port, No via usb!. I have Oldis Pc's only with Parallel port it doesnt have enought power for ISA cards with usb 1.1 ports or pci. The LS120 SuperDisk (ext) is an option but i 've a many 3"1/2 fdrives (int) to use like an externals. Idont want a zip's iomega, Help pls.

Brilliant mate!👍

Hi George, You have done a great job and I really appreciate all you have done. I am trying to use your circuits . I am going to review all your videos , circuits and software. I will probably use a z80 first then a 6502 bread board. I am currently using a fd55-gfr floppy and have the 74hc273 driving outputs to the drive . I just wanted to thank you for the effort you have put in.

excellent

🤣@12:02 Hungry?

James Sharman recommended this series.

@41:50 maybe "soft sectors"? The Amiga used an encoding which resulted in a special byte pair (0x4489) that could not be generated by the encoding so if that ever occurs in the data stream you know it is a sector start. There are other combinations which got used in some disk protection systems. When it read a track, it didn't have to wait for the start of a sector, it just dropped the heads and read an entire track into a buffer. The cpu then looked for the soft index word and used the blitter to move the two halves of the buffer.

Wouldn't it be easier to just use a data separator chip like WD9216 (for data & clock separated) .. and a controller chip like FD1793 ?! .. please make a video explaining a similar setup like that ;) .. Good work!

What are the part numbers for all of the gates used thanks in advance

Super cool, plan on using your design as the basis for a sound card for the Minimal64x4

Thank you for useful tips! I'm so happy I invested some time to learn KiCad basics. Now I have access to a huge library of symbols and footprints without detail sacrifice. Yes I have no nice stripboard background like in Fritzing or VeeCad or DIY layout creator. But it really doesn't matter. More over an ability to route only needed strips makes designs vastly more clear to work with and gives you nice zero-thinking points to cut strips on a real strip board.

This memory code for all the characters you’ve wrote in the eprom, have you any idea where is it located in a modern computer?

I feel like the c64's floppy drive solution was the exact opposite answer to "How can we build a cheap, fast, and simple to use floppy drive"

Hi! Awesome work! As for the random bugged lins in the read images: You're supposed to check the CRC and retry a read if it's incorrect. Its perfectly normal for reads (and writes) to fail randomly from time to time, depending on many factors. Also, where's is the next part? :-)

You absolute legend! I couldn't get out my quadraverb eprom and i used your trick with gaffer tape. it came straight out! Cheers!!!!!

i wonder why microsoft chose 1.44 mb and 1.2mb and 1.68 mb dmf for its floppy disc formats too? thanks.........

why did Acorn choose 640k, 800k and 1.6 mb for its floppy disc capacities ?? thanks....................

"Hello, I want to do something like this. I have an old system that only has floppy drive and parallel port outputs. Data is read and written using floppy disks. I want to disable the floppy drive, connect Arduino to that port, and use the system as if writing to a floppy disk to save the data to an SD card. Do you think something like this is possible?"

I checked and almost all those primes are odd numbers, I could only find one that wasn't.

Those sockets are for cpu cores?

Hi George, I just watched all your 6502 based videos and think you've done the most amazing stuff I've ever seen with the 6502! Really impressive! In 2020 I got the Ben Eater kit along with the video card kit and ended up putting them together. I decided to take it all apart a few days ago and start fresh so I've been reviewing my assembly coding skills and browsing methodologies before going into creating my own design and eventually PCB. One thing that was a big flaw with the eater 6502 was not enough VRAM to display to the whole screen, since he used every (6502 sized) pixel for every memory address and having to pause the CPU to allow the video card to access VRAM. After watching all your videos and techniques I was amazed of what could be improved on, and I also came across how the NES did it using a PPU and only 2KB of VRAM, so now I have no idea where I should really start. My main goal is to have a 256x240 screen resolution just like the NES, sprite capability, 64 colors (or less if necessary) and maybe extra memory banks using the VIA if necessary. I think it would be cool to have a kernel like Wozmon on it that is interactive over serial, so I can interface a keyboard, and launch programs with some games I've developed, or use a midi interface to write/play some 8-BIT music. I think the hardest thing to sort out is the video interfacing, and sprites, and what would be the most sensible way of dealing with it. I would greatly appreciate your input. Thank you.

Thank you, worked perfectly on my quadraverb gt eeprom replacement!!!

It would be used to program SST49LF020

lol click this video and you immediately mention the capacitance problem I commented on the last video I am 100% gonna build one of these for my 4 bit computer, I'll give you the credit for the design cause there's no way I could have thought of this

mosfets are very sensitive to electric fields and circuit capacitance I'm fairly certain that the reason the LEDs stay on longer when you have the static memory on is because of the circuit capacitance which is generated with them on, this is also the reason that if you leave the static memory on long enough and refresh the dram that it lights up; the circuit has been slowly charging the wires with capacitance until they are saturated and this is enough to trigger the mosfets, this is a huge problem in ICs and alot of the design goes into preventing this sort of thing this is also the reason that the rows on the right drain faster; they're closer to the power supply and thus they drain from the ground/hot states, the rows to the left of them are maintained by the capacitance of the circuits to the right, it's fascinating how circuits can have such a dramatic effect on one another without being physically connected

I found this video after I was trying to design my own ram, using only 4 bits would take me 110 transistors, I am fairly certain I over-engineered it lol

Can you get the complete circuit diagram so that I can understand what quality components are used at which place. Thanks

Did you used fixed point or floating point to do the calculations?

I want to see part 2

Very cool that you show the mistakes and failure modes so that we can learn to recognize them as well.

Can you make a video on how to use a 82C450 VGA Graphics Controller instead of all thoes chips please 🙏

😀 "Promo sm"

wow i didnt know the 6502 can run windows

This is useful information, and I like the gradual build-up of resolution. I'm currently building a near clone of my first computer from 1979, the Microtan 65, but with a W65c02 clocked a lot faster than the original, which was 750kHz. And of course, I'm using better RAM and EEPROM.