New Rs232 cartridge - checking interest | MSX Resource Center (Page 3/5)

Par anonymous

incognito ergo sum (116)

21-01-2015, 17:07

I'm not angry, sorry if that was the impression I gave. Should probably use more smileys.

However, the way you asked made it sound as if I had to justify my interest in an RS-232C interface.

Par karloch

Prophet (2159)

21-01-2015, 17:17

I would be interested in one according to JaviLM specifications.

Par ericb59

Paragon (1099)

21-01-2015, 17:33

Here the technicals details of the RS232 interface I want to clone
http://msx.hansotten.com/uploads/msxdocs/sonyhbm232sm.pdf

My basis is that, after... perhaps it will be more powerfull.
My own interest is this interface have A rom with Basic instructions.
That's why i plane to make this one.

Par anonymous

incognito ergo sum (116)

21-01-2015, 17:44

ericb59 wrote:

Here the technicals details of the RS232 interface I want to clone
http://msx.hansotten.com/uploads/msxdocs/sonyhbm232sm.pdf

These super-detailed manuals amaze me.

The UART in that schematic is an 8250-compatible. These suck because they don't have an internal buffer and the Z80 has to be careful not to miss an incoming byte.

Ideally you would replace it with a 16550-compatible, that supports up to 115200 bps and comes with a 16-byte internal FIFO buffer. However, I' don't know whether a 16550 would be pin-compatible with the one in the schematic.

Par rolins

Champion (418)

21-01-2015, 17:44

I'd be interested in buying one.

Out of curiosity, will this work with MSX1 computers with 32kb Ram?

Par ericb59

Paragon (1099)

21-01-2015, 18:14

Eugeny Brychkov is working on designing this interface.
I will ask him if he changed some chips.... But I think he already done some adjustments.

@rolins : I don't know. Check the manual...

Par MsxKun

Paragon (1115)

21-01-2015, 20:38

An new RS232 interface? Usually I never needed one, but some time ago I got a Soundgin, a little card with a soundchip that can be programmed using RS232 and I borrowed one for my MSX to make it sound using the fossil driver. It was successful and then I returned the RS232 (tho the owner didn't deserve it!! ) so it would be interesting to get a new one.

Par Manuel

Ascended (19310)

21-01-2015, 23:01

Note that the Sunrise RS-232C interface uses the 16550. What about using that one, if you can find a 2nd hand one of course (or one which also has IDE in it...)

Also, that Sunrise RS-232C was designed by Erik Maas. Perhaps he wants to open the design if there's really interest in it.

(Or what about using an SD card to exchange data? ;-))

Par anonymous

incognito ergo sum (116)

22-01-2015, 03:09

Manuel wrote:

Note that the Sunrise RS-232C interface uses the 16550. What about using that one, if you can find a 2nd hand one of course (or one which also has IDE in it...)

I used to own one .That would be a nice solution if they were still produced. They're not.

Manuel wrote:

Also, that Sunrise RS-232C was designed by Erik Maas. Perhaps he wants to open the design if there's really interest in it.

That would be wonderful.

Manuel wrote:

(Or what about using an SD card to exchange data? ;-))

Ok, Manuel, now I'm beginning to think that you're actually pulling my leg here. :)

Eric's original question was: "I may produce an RS232C cartridge if there's interest. Are you interested?", to which I replied that I am. This discussion about alternatives, while technically correct, is beside the point. Especially when the alternatives aren't produced or sold anymore.

And no, I'm not angry. :)

Par Manuel

Ascended (19310)

22-01-2015, 15:20

JaviLM: it just feels like a step backwards to me, to use RS-232C in 2015, even on MSX. That's why I'm coming with all these alternatives, which are a lot more modern (yes, especially on MSX .

Of course, everyone is free to do what he likes If you enjoy RS-232C, have fun!