MiSTer FPGA Forum

I would just say, that FPGA simulation of hardware does have it's place, and would boil it down to SNAC and controller latency, and display output lag. This is more true especially on older systems and arcade machines. No PC emulator could possibly eliminate controller input lag, and that drastically reduces playability of some titles to the extent...

TL;DR Original developers of the core: Is some newer version of ao486_tool to generate autogen directory available ? I have trouble generating same content with tool from Aleksander's original repo. Now to the actual saga. I love hacking into ao486 core. More and more I am going through the code, more respect I have to all the people who made this ...

There is a reason for using 5CSEBA6 Altera/Intel FPGA. Because it is used in education kit, this part is supported in free version of toolchain ( Quartus Lite), and the price of the whole kit/board is (was before chip crisis) nowhere near of unit price of FPGA chip itself. Also, it is a SoC FPGA with ARM cores. Artix-7 7A200T does not incorporate A...

It seems that he goes very much like the same path I was going last year. If there is no MCU used it means that he needs to do some form of logic IO expansion, possibly by shift register/latch. This was not reliable in Amiga core at all. I was just not able to meet timing needed for proper floppy drive control, even with some most critical pins con...

I've also made a very bodge setup on DIY two layer board to test Pi Zero 2W out. Only if I made display+buttons aligned with MiSTer buttons+leds and move Pi Zero 2W to the back and align SD card with board edge..... To be fair I was trying to make it as slim as possible, and made it wider with two additional mounting holes at the last moment. I rea...

Posting patches & compiled binaries with updated write code. Could you possibly look to get some of the floppy controller improvements merged? There's no reason they shouldn't be if they achieve more accurate behaviour. To be completely honest, I just can't figure out how to integrate it properly and not compromise any other MiSTer functionali...

I thought this PIN was needed to format a DD 360K 5"1/4 floppy disk inside a HD 1,2M floppy drive. Is it true or false? To be completely honest, I don't know how it was on 5"1/4 drives :). 3,5" PC drives are configured by hole on floppy disk, this selects between 1MB and 2MB total capacity with 300rpm. With DENSEL pin active, DD dis...

UgoR934, the I/O list is correct. The header connection list is not. I did a quick recheck, and came to this: O - USER_IO[0] - AG11 - ARD_IO15 - DRVSELB O - USER_IO[1] - AH9 - ARD_IO14 - MOTEB O - USER_IO[2] - AH12 - ARD_IO13 - SIDE1 O - USER_IO[3] - AH11 - ARD_IO12 - DIR I - USER_IO[4] - AG16 - ARD_IO11 - DSKCHG I - USER_IO[5] - AF15 - ARD_IO10 - ...

Posting patches & compiled binaries with updated write code.

C5484 wrote: ↑Sat Dec 19, 2020 6:41 pm so if i understand correctly, for those who want to replicate your results need a DE10-nano, some wires, lvl converter and a PC floppy drive

Exactly.

C5484 wrote: ↑Sat Dec 19, 2020 6:41 pm I am designing and building a plastic case for the MiSTer, incuding a keyboard and the FDD.

Looking forward to it !

I've a small batch (qt. 8) of CD4050, Sure, these can be used, if they are powered with 3V3 supply. if you have a photo "closeup" of wires of your board You simply don't need any. Everything is on Arduino header on DE10-Nano. If you have analog I/O board, some pins are populated, and connected to user port. Some are not populated at all,...

I don't have the I/O board in this house to double check directly on that PCB if something etched over there can help finding out. If you don't have I/O board, the job is far simpler. Just use DE10-Nano manual, pages 30 and 31. There is Arduino header pinout. As I posted earlier: PIN_U14 IO_SCL STEP PIN_AG9 IO_SDA TRACK0 PIN_AF17 USER_IO[6] DSKRD ...

Update: I've corrected some bugs here and there, and added write precompensation logic. Write precompensation follows what is in original Amiga, so there are four levels: 0, 140, 280 and 560ns. I've thoroughly disassembled and cleaned old SFD-321B drive from Samsung to test with, so I have perfect specimen of a very common drive out in public. Does...

Yes, this was mainly for those who wanted to experiment before any release. I could post gerbers for CPLD version like in the video, but you would need a way to program Xilinx device, so I wasn't even thinking about it. I still want to use only a user port, and create board for this user port version, like it was in renders. It is also possible, th...

Wont it also need that USB board? The first point does not seem to go into that. Dont you have a board blueprint for that or something that we can then either make ourselves or order from some PCB maker? Actually, no, you don't need that board. In this GPIO version, that board serves only as a level converter with open-drain outputs. You just crea...

I was a little bit busy with family christmas meetings over the previous weekend, and my current daily load at work is also bigger, so I am sending here the exact same source code, as was used in the floppy video I sent last week. I wanted to work more on this before releasing anything, but it could take considerable amount of time I don't currentl...

A quick update: Below is a link to a video file showing MiSTer Floppy working with read, write, and DFx selection in MiSTer menu. It is still work in progress, there are still some bugs to catch. First, there is a blank/erased floppy inserted under XCopy as DF1. It shows that it is not a DOS disk. Next, it is written with Workbench image from ADF i...

retrorepair wrote: ↑Mon Dec 07, 2020 10:17 am Do you mean an error when using clk_sys? Have you created a PLL for 50mhz?

No, I meant slight error in producing exact 2us out of 7,09379 MHz clk7_ena for write bits. But it was overdone, there is always error in motor spinning, so there is no point doing it exact. I've redone it using clk7_ena, it integrates much better.

On the 2-floppy quesion, I'd say only pursue this if it doesn't hurt the overall aim of having a simple stable device and config. Besides, we know sorg generally avoids things that are needlessly complicated, so keeping it simple might help sell the thing to him. Yeah, I will probably stick with just one drive for now. I am planning on using only ...

Will it be possible, after the adapter is finished to add Floppy disk support to other cores from computers that had floppy drives back in the day? Or is this an Amiga exclusive? TBH my primary interest is Amiga. I have floppy drive associated with that computer. But my primary objective is to wire the floppy drive to MiSTer in dumbest way possibl...

Update: I created better prototyping board. This board should be fully usable as floppy adapter, there are some connectors which are not necessary for actual function, and JTAG connector can be way smaller. It is still more about experimenting than actual production-ready hardware. I needed to do this because of write support, I hadn't enough conne...

Excellent work. Will this hardware support a real Amiga floppy drive also instead of just a PC drive? Hopefully you will be able to add a jumper to pick either an Amiga or PC drive. I have prepared prototype interface with both PC and Amiga floppy drive in mind, I want to have floppy drive type selectable via MiSTer menu. This could be a drawback ...

kolla wrote: ↑Sat Nov 28, 2020 2:07 am Big question is - does it click? Will noclick commodities work, or break the hardware?

You mean that clicking sound when no disk is inserted ? Short answer: Yes, of course it clicks .

This being said, do you think that the physical disk could be addressed to DF0: instead of DF2: (In another way than using the early startup which doesn't work for games) ? There will be selection possible in MiSTer menu in floppy configuration, you should be able to select DF0 - DF3 as physical floppy, blocking ADF emulation access to the same dr...

Update: Reading is done. I think I've resolved all bugs in physical floppy controller FPGA part. I've actually found out, that the ADF read speed should match real hardware, as it is using 3 DMA slots, if "Floppy disk turbo : off" choice is selected in MiSTer menu. I needed to replicate this on real floppy, and found out some more bugs in...

Also, some more update - since I still do not have parts (timeframe unknown) to be able to build a prototype version and I am still stuck with breadboard, I did improve DPLL to further mimic original hardware. I am very satisfied with the result, XCopy can read the whole floppy without retries. Posting how the real floppy is integrated into Minimig...

Ok, I get it. Why on earth I am doing such thing, if there is nowadays almost no possibility to buy new floppy drive, and floppy disks are way more expensive than before: 1) At first, I wanted to do just a weekend hobby project, to bring back nostalgy with drive sounds, and to be able to do some proper disk juggling. I still have my old Amiga disks...

Ahhhhh, I was utterly stupid and did some huge mistake in floppy drive output gating logic. It works, and I have my first full floppy read on MiSTer Minimig core from physical floppy drive ! Please note, that it is substantially slower than ADF read, it takes 23 seconds for XCopy to read whole virtual ADF floppy, while it takes full 1:15 minutes to...

Just a quick update: It (almost) works ! I've managed to integrate floppy reader into Minimig core, modifying Paula functions to use physical floppy drive as DF2. DF0 and DF1 is still mounted via HPS as virtual floppy drives. As you can see in the attachment, I've managed to sucessfully insert Workbench 3.1 Install disk into physical floppy drive a...

Well, adding another USB-B, USB-microB or USB-C connector would be odd.... I think extension will work for those who want to have it somewhere else. I didn't think of floppy drive power supply yet. There are floppy drives with 5V and 12V supplies, and there are floppy drives with 5V only. I didn't looked into DE10-Nano schematic yet, there are thre...