Raspberry PI as a real Amiga Floppy Drive

[kriz]

Great progress Kipper !!

[mram]

Wow! Cool, lot of people will appreciate that!

[alexh]

If you can implement a single RaspberryPi GPIO as a digital eject button that would be cool. It would allow the emulator to support multiple stacked disk images without an LCD or anything.

Even cooler if you could come up with a physical mechanism which would allow the use of the three (?) different eject plastic tabs (A500, A3000, A600/1200)

[mram]

Originally Posted by alexh

If you can implement a single RaspberryPi GPIO as a digital eject button that would be cool. It would allow the emulator to support multiple stacked disk images without an LCD or anything.

Even cooler if you could come up with a physical mechanism which would allow the use of the three (?) different eject plastic tabs (A500, A3000, A600/1200)

Actually the eject is the "disk change" button, it is supporting 4 disks stack per drive (so 16 disks...). This to change on the fly.

IMHO for games this isn't an issue, you load the disks needed on the disks menu (and it is easy, you select the first disk and then you press return to add to the current stack or enter to add to the next stack or F1-F4 to add to related stack) and then press "disk change button" to pass to the next one.
If you have to load another game, you should reset the system, so you go back in the disks menu.

For workbench this could be a limitation now but, IMHO, if you really need to have this option in workbench perhaps you could buy a hd emulator (like that kipper2k did or ACA-500) which provide for 80euro or less a much faster way to work with also memory improvements (8mb for the kipper2k), Compact Flash slots and Roms selection.

Anyway, this doesn't mean we don't have to improve the project!
So I don't understand exactly if the behavior of the "eject" button is the same of "disk change" button.

Someone ask me to add an UP/DOWN button to load previous/next disk, but IMHO this is useless in our scenario and in case you have hundreds of this, I have 3500... can you imagine?
Video, usb, ethernet, audio are already on the board, we just need time to use it in some way, they can be enabled just by software updates (just copying updated files on sd ), but GPIOs on Raspberry PI are limited, so we have to take care of it, if we want to use for future features. And for this I need your all opinions (sure there are a lot, sure it will be a config file...:-) ).

[alexh]

Originally Posted by mram

So I don't understand exactly if the behavior of the "eject" button is the same of "disk change" button.

Yes we are talking about the same thing.

But I am suggesting rather than two nasty red and black push buttons, we position/align a single phyical button on the PCB (plus any clips / mechanicals we need) to make it physically work with the different shaped plastic eject buttons which can be removed from the old floppy drives and fitted to the new PCB.

It would look so much better. Don't you think?

I don't see a need for a 2nd button. Use just one and like a Mac one button mouse make it time sensitive. i.e. Write the software so if you keep the one button pressed for less than 5 seconds it is a disk-change, 5-10 seconds and release it triggers "Setup Mode" and hold it for 10 seconds or more and it goes to "Write to SD"? (or something like that)

[kipper2k]

I'm not sure exactly what you mean about the buttons Alex, I can position buttons etc pretty well anywhere in the floppy slot, or even add a small daughtr board that can be secured at the back of the case to allow usage while the buttons are in a safe place away from accidental knocks.

A timed single button would be a good option. Held in for less than 1 second perform one function, pressed in for >2 perform another function. could fancy it up with an LED for visual indication too if so desired. 5 and 10 secs would be too long, maybe even an option in a config file to further enhance it

I made a couple of changes to the design (I updated the picture), major one was relocating the a500 34 pin floppy header further right. The cable can be easily connected now with just a simple 90 degree turn of the cable to make it nice and tidy. Also, i widened the slot a bit to allow 34 pin cables that have the extra clip on it to feed through ok. I added the mounting hole for the a500 so the board should now mount fine in the a500, a600 and A1200

[mram]

I have to admit the buttons I used are really horrible! I search a little bit some more Amiga-style... not found.

Yes, I agree, better is the timed buttons option. Timing can be in a config file, this can als free 1 GPIO (Yuppi! ). I don't remember why I didn't it before, perhaps because I started as external drive...

Thank you

[kipper2k]

Originally Posted by mram

I have to admit the buttons I used are really horrible! I search a little bit some more Amiga-style... not found.

Yes, I agree, better is the timed buttons option. Timing can be in a config file, this can als free 1 GPIO (Yuppi! ). I don't remember why I didn't it before, perhaps because I started as external drive...

Thank you

I found a through hole momentary on switch that should be perfect. The button should easily poke through the Amiga to allow pressing...

http://www.digikey.ca/product-detail...2615-ND/502079

This one has a usable overhang of just over 1/2" which should be plenty to allow easy pressing

[Solo761]

In regards to LCD, you could probably use I2C, for standard 1602 compatible LCDs there are premade cheap adapters. That'll reduce required number of wires needed to two.

But if it's purpose would be ADF navigation that would mean you'd need at least three buttons (up, down, select/open) which would also take three GPIO lines so that would be 5 lines all in all if I didn't forget something

[mram]

For the external display I would like to use the cvbs and/or hdmi to connect as source to the tv or to a little monitor like this http://www.banggood.com/4_3inch-LCD-...R-p-75120.html

Advantages of this choice:

- great display, colors, graphics (proportional well defined fonts), it is more than 4 rows and 30 or more columns, scrolling, screenshots or logos possible
- cheap, less than 18$, no need interface
- you can choose to connect video output to this little LCD or as cvbs/hdmi source to tv
- don't need extra GPIOs

Disadvantages:

- power, the model I have use less then 2W which is ok, others around 4W so need to connect directly to 12V from Amiga power supply connector or from an external source

In past I used in my tests a 4x20 LCD display, which is the minimum display to have a good feedback overall if we use 4 drives, but it also require power we should get directly from power supply, and at least it isn't so cheap.

So by now, because it's a good option to use in any case the free RPI video output and for who just don't want to build/buy other hardware, I'm just following this way, after that we will see how it looks and we can choose.

Also for buttons to choose the disk to insert (see my previous posts too), IMHO 2-3 buttons are not so good to choose a disk if you have more than 20 games, pressing several times up/down when you have a keyboard just in front of you (& a nice menu when you start to use Amiga...).
When you have 4 drives and you can load 16 disks, when you really need to insert another disk? It seems to me this is possible when you use Workbench, but we can think to make an amiga program for Workbench (like the starting menu) where you easily choice the disks you want to use. In this case also consider to buy something like ACA-500 or the kipper2k board, they will really improve several factors of your experience (just another level) and they are good priced ~80euro for what they do.

Finally if we see it is really convenient add LCD/buttons or whatever, there are GPIOs like the one for the led or the one for second button or the other 4 GPIOs from the header P5 we can use too, or other possibilities, so it isn't an hard limit.

Let me know what you think about that.

[Solo761]

Of course, having "real" screen is a plus, and since I use ATX PSU I don't see any downside on that part . To me only downside is that it takes space while 16x2 LCD is rather small. And can even be integrated in the case. Or in other words, HxC like setup.

But you're right, it's not really all that practical to browse few thousands ADFs with only few buttons . Although current setup doesn't need a screen, 16x2 or 16x4 screen could be used just to see which ADF exactly is mounted (in case you have few to cycle through).
It would be possible to make use of one of 16x2 or 16x4 screens over I2C and also make a keypad that would be daisy chained to screen since this is possible with I2C. Let's say classic keypad and small MCU, PIC or Atmega, that would register them and send them over I2C chain to rpi.
This can even be used with fancy screen like you're planning, some kind of custom keypad to navigate and it would use only 2 GPIOs.

Problem with these homebrew stuff is that everything is possible and you can easily go overboards . Truth be told even current version is wooow .

[alexh]

could you genlock the pi composite and the amiga rgb? should be possible

[lukassid]

Screen like that could be mounted in Amiga case!
http://www.ebay.co.uk/itm/1-8-Serial...t/360762749239

[kipper2k]

If using a card with thousands of ADF's on it then obviously there needs to be a simple way to get to the needed image. For my Amigas i break down the WHD games into group file structures , example 0 - E, F - J etc so that the Amiga does not have to scroll through lots of listings. and within those directories i use a subdir structure, there may be a few directories but in a slower Amiga it is much faster and easier on available memory than listing all the games in one mass Directory. If the button(s) could be set up to make it easier to cycle through available directories then that would be great.

[alexh]

Originally Posted by kipper2k

If using a card with thousands of ADF's on it then obviously there needs to be a simple way to get to the needed image. If the button(s) could be set up to make it easier to cycle through available directories then that would be great.

There is no need for an LCD or any need to navigate the card using buttons.

Disk selection should be done using the Amiga.

On power on the Pi should present the Amiga with a default disk image made up of a floppy manager program and the directory structure of the card.

This floppy manager program would be a native amiga program and run on the Amiga, displaying the directory & files on the TV. Disk selection can then be done using the Amiga keyboard. The choices are sent to the Pi via the floppy cable.

Going back to the default disk image (and the floppy manager) when you're finished playing (without power cycling) can be done using the "eject" multi-function button we discussed earlier.

[lukassid]

You going to program that?

[Amiga1992]

Really interested in this board of yours kipper! Let me know whenever they are for sale, I want one.

[mram]

Originally Posted by alexh

There is no need for an LCD or any need to navigate the card using buttons.

Disk selection should be done using the Amiga.

On power on the Pi should present the Amiga with a default disk image made up of a floppy manager program and the directory structure of the card.

This floppy manager program would be a native amiga program and run on the Amiga, displaying the directory & files on the TV. Disk selection can then be done using the Amiga keyboard. The choices are sent to the Pi via the floppy cable.

This is how it actually works .

Going back to the default disk image (and the floppy manager) when you're finished playing (without power cycling) can be done using the "eject" multi-function button we discussed earlier.

If you use Workbench is ok, if not (you are playing a game) this isn't possible. There isn't actually a way to freeze the amiga and start another program (the floppy manager) to choose the disk. This is THE issue.

[mram]

Originally Posted by Solo761

Of course, having "real" screen is a plus, and since I use ATX PSU I don't see any downside on that part . To me only downside is that it takes space while 16x2 LCD is rather small. And can even be integrated in the case. Or in other words, HxC like setup.

But you're right, it's not really all that practical to browse few thousands ADFs with only few buttons . Although current setup doesn't need a screen, 16x2 or 16x4 screen could be used just to see which ADF exactly is mounted (in case you have few to cycle through).
It would be possible to make use of one of 16x2 or 16x4 screens over I2C and also make a keypad that would be daisy chained to screen since this is possible with I2C. Let's say classic keypad and small MCU, PIC or Atmega, that would register them and send them over I2C chain to rpi.
This can even be used with fancy screen like you're planning, some kind of custom keypad to navigate and it would use only 2 GPIOs.

Problem with these homebrew stuff is that everything is possible and you can easily go overboards . Truth be told even current version is wooow .

Yes, this is what I was thinking about other possibilities, if we need we can connect the RPI to a chip like attiny2313 (or something like that) using i2c or serial and then we could attach all the LCD/keys we like (the 128x160 1,8" seemed cheap but too small IMHO).
I tested this early, this is a video

[ Show youtube player ]

While it is enough to see all loaded disks, up to 16, it seems not so good when you have to deal with thousand (how many do you have?) even if you break it for instance using first letter as folder. At least, I dislike up/down button, much better to have a rotary encoder, a wheel with a good program could be a viable solution.

[alexh]

Originally Posted by mram

If you are playing a game this isn't possible. There isn't actually a way to freeze the amiga and start another program (the floppy manager) to choose the disk. This is THE issue.

All you need do is on the Eject event switch back to serving the floppy manager disk. Then the user resets the Amiga with CTRL+A+A. Just like they would had changed disks physically.