Minimig PCB run - interest thread

[little]

If the FPGA is upgraded from 400k to 500k gates there should be enough room for a 65816 or a 68ec020 core inside it. At the present time I do not think somebody has written any of those cores, but when it is mass produced I think somebody will write them since the source of software emulators for those (and many other) CPUs has already been made public.

[little]

I am thinking, an added bonus (besides de extra 100k gates) the XC3S500E FPGA has over the XC3S400 in the actual design is that it has a "Low-cost, space-saving SPI serial Flash PROM". What use would that be? Take a look here and scroll down to place where it says "SD card proto pcb". If such a design could be added to the minimig then no PIC controller would be required at all; that is, if the extra code to access the SD/MMC card as a floppy disk (or hard disk or CD-ROM) can be put inside the FPGA.

[little]

I was also thinking, if the 68k is succesfully placed inside the FPGA, that means there are enough free I/O lines to do one of the following:

A) IDE disk interface. Albeit if hfs (and maybe iso) support for the SD/MMC card is added it might be a little redundant, it does open the posibility of using one of those cheap IDE to SATA or IDE to CF adaptors.

B) Floppy drive interface. Albeit if write support for adf files is added and ipf support is written it might be redundant, but if it functions like the catweasel adapter (reading all kind of floppy disks) it might be very useful.

C) Parallel port. For people with amiga friendly printers, people that still have one of those ZIP drives or people that have one of those adapters to add two extra joysticks. It might also be used to implement a video slot.

D) SCSI port. If the A570 expansion/A2091 card is implemented in full, it would allow a real SCSI port (besides a virtual SCSI hard disk via hfs files) to connect external scanners, hard disks, removable media. etc.

[little]

TobiFlex wrote:
The 68K is succesfully placed inside the FPGA by me! Also the SDRAM Controller and the Spihost for floppy emulation! You can try it if you have a DE2 Board from Terasic.

I hope i can finish the port for the DE1 Board next week.

Viele Grüße
TobiFlex

Cool! Please keep us posted :-)

As a side note, can anyone tell me if it would be posible to make this external parallel port floppy drives read amiga formatted disks? If it would be posible then a parallel port would be the best option, specialy since it might be feasible to dinamically change it from parallel to scsi :-D

[little]

A regular PC internal floppy disk (or a DELL external laptop disk) would be perfect though.

Mhhh, how about adding a selector header (like the one that selects 15/31 khz) to select if the minimig has an active internal floppy interface or an active external parallel port? Chances are people will not need both (or at least will not use both at the same time).

Just thinking out loud, as usual  :-)

[little]

alexh wrote:
I think Parallel port and external floppy disk drive are the the same connector.

Sadly, the amiga external floppy port is a db23 and not a db25. Besides amiga external drives (low or high density) are expensive and hard to get, while internal pc floppy drives are cheap and easy to get, that is why I though of an internal floppy interface.

If you had a minimig with this connector (and an FPGA with enough I/O) All you need is a different MiniMig "image" on the SD card to switch between parallel port or real floppy disk.

That would be cool!