new Mega 65 prototype pcb - connectors

append delete adtbm


i have a question, i have just seen the pictures of the prototype Mega65 board.
i was not able to see any connectors for the SID(s).
Are they still in the planning ?
That there is no Tapeport i knew already from recent podcasts, what is with the Userport ?

Can you maybe post a board description, what connectors are there ?
(Of course, seriell, joystick, etc., is obvious)

Thanks in advance and i just wanted to say, the board looks great. (Even if it looks a class harder to solder at home, compared to the previous widget board (and that one was allready challenging)).

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append delete #1. gardners


The final set of connectors has not yet been settled. What there is currently, is:

* C65 keyboard
* IDC header with keyboard pins (will probably be changed to a C64-compatible keyboard connector)
* 24-bit VGA out
* 24-bit HDMI out
* 34-pin standard floppy drive connector
* C64-compatible cartridge/expansion port
* 3x PMOD connectors (common on FPGA development boards)
* 50-pin IDC expansion connector
* C= serial floppy drive port
* Connector for USB serial debug
* Power switch
* Reset switch
* Joystick ports

As I say, the final list of ports may end up somewhat different. What is likely for now, is that if you want a tape or user port, these will probably connect via a PMOD or the 50-pin expansion connector. The lack of these physically large ports all comes down to cost. The bigger the PCBs, the more expensive.

We do hope to add sockets for SIDs. Worse-case scenario, they will be usable from a cartridge.


append delete #2. adtbm

Thanks for the answer Paul !
I like the decision, to maybe make the Tape/Userport optional attachable via PMOD, or 50-pin IDC.

If i may ask one more question: What will be the operational Voltage ?
Since the SID operates with +5VDC and +9VDC/12VDC (8580/6581)
and the FPGA normally runs on 3.3VDC, will the Voltages be generated onboard, will you be using transceivers again (Like on the widget board)?
What are your plans regarding this ?

append delete #3. mega65lover

paul......CAN the sid be on cartridge????

append delete #4. zeha

so there will be no analog composite video out? only vga and hdmi?

append delete #5. PGSmobile

On a normal C64/65 can't have SIDs on the expansion port, however the MEGA65 is designed to do this. In fact, support has already been added (but not yet tested). The cartridge would have its own audio out jack.


append delete #6. mega65lover

I want this!!! want SID on expansion port!!! I WANT THE CARTRIDGE SID NOT BUILD ON BOARD!! EEEEEEEEeee! -fans face- that is hot!! NOW MEGA65 IS A TRUE TOY! TRUE CONSOLE!! heheheh :D

append delete #7. mega65lover

I want it like MSX...all expansion hardware through cartridge...I want lots of mega65 games on cartridges..much like a console!! So coool!

append delete #8. gpz

On a normal C64/65 can't have SIDs on the expansion port

of course you can - and it even was the first SID expansion for c64 ("SID Symphony cartridge")

append delete #9. gardners

@gpz: Yes, you can put anything on a cartridge, I meant in terms of having the address lines properly decoded. Of course, SIDs being mostly write-only they are easier than some other things to put there. Sorry for not being entirely accurate there.

@zeha: We haven't made a final decision on composite output. We can in theory generate it directly from a very rapidly switched FPGA pin. There are some complications, but we are still considering it.

@mega65lover: Well, you might get more than you wish for there. The trouble will be if you need lots of things on the cartridge port at once, as it may not be possible to have them all connected at the same time due to various complexities.

@adtbm: re tape and user port, we expect that there will be an adapter for the expansion port that will allow it to be used instead as user port + tape port, but it might not be available immediately.

Regarding operational voltages, we have voltage level converters where they are needed, so all chips that expect 5V signals will get them. 9V/12V for SIDs we don't yet have the final solution for. If they are in a cartridge, then they might need a power supply lead of some sort to the cartridge. If we put internal SID sockets, then we will supply at least the 12V signal.


append delete #10. mega65lover

quote from gardners: @mega65lover: Well, you might get more than you wish for there. The trouble will be if you need lots of things on the cartridge port at once, as it may not be possible to have them all connected at the same time due to various complexities.

reply: heheh! I am ok with that :D

append delete #11. zeha

@ composite out: it would be VERY cool if that would be possible, as e.g. in my opinion this is the coolest thing about the Raspberry Pi - they offer HDMI and Composite, which makes a lot of uses possible. And I frequently use both of them, depending on my use case. VGA is something "in between", and I feel like its relevance today is somehow questionable. But having HDMI and Composite is something like the combination of most modern interface (HDMI) together with lowest common denominator (Composite).

I think many people would like to use it on a modern TV, for those HDMI is perfect. And also many people would like to use it on old monitors like 1084S and so on. I personally use a Sony PVM. So you could please both crowds with that. Of course I don't mind having VGA as well - but I think having Composite would be more important.

Another thing that might be possible to consider would be S-Video. It offers better quality than Composite, but as far as I know, Composite is "just" both of the S-Video signals combined, so it shouldn't be hard to convert from S-Video to Composite. But as far as I know, converting from VGA to something else always requires dedicated (and powered) hardware.

Maybe S-Video is easier to do for you than Composite?

Of course in the end it's your decision what to use, and I understand that there might be technical reasons for leaving it out. But not being able to use the MEGA65 with old Commodore monitors etc might put off quite a few people, that's at least my assumption. So I would really really love to see Composite or S-Video on the final product :)

append delete #12. mega65lover


I agree. In fact, if there is composite..myself I will never use HDMI.

append delete #13. jcook793

I am very excited about this project, thanks for spending so much time on it!

This thread is about connectors. I hate to ask for *even more*, but in my dreams there would be some sort of Bluetooth connectivity for keyboard/joystick/headphones for some late-night programming/gaming sessions from the couch. Any hope for that setup?


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