Sporny Kun

The STe, like the STF, has moved the joystick ports away from the motherboard, and put them on the keyboard assembly. The 520ST (first version, short case, no integrated floppy, no integrated power supply) is then quite different. I have an ongoing project for this model, the PCB is far from done, but the schematic is usable though : https://github.com/sporniket/kicad-conversions--atari-260-520-st-motherboard--c070231 A pre-release of the PDF is available here : https://github.com/sporniket/kicad-conversions--atari-260-520-st-motherboard--c070231/releases Hope this helps.

Seems nice, I wouldn't mind a ST version

No idea. You should check the schematic, or test continuity between RAS and the RAS pins of each DRAM

Hello, SDRam can be seen as a grid of memory cells, thus organized primary by Rows (R) and secondary by Columns (C). Thus, basically, to access a given cell, the computer (the MMU in the ST if I do not tell a mistake) first specify the Row on the address lines of the SDRAM, and send a pulse on the... Row Address Strobe (RAS) line. Then the Column is specified and there is a pulse on the Column Address Strobe (CAS) line. There are optimisations, because when a row is "opened" as they say, one can request for a few columns, and thus save some time. There are also limitations, as a SDRam needs to "refresh" all the grid regularly (think of each cell being like a kind of capacitor that lose it's charge overtime). On another topic, to test your RAM, there is a program, YAART if memory serves me right, that could be of use in your case : http://www.chzsoft.de/site/hardware/diverse-kleinigkeiten-fur-den-atari-st/#ram-test-software-yaart

Interesting, thanks for the feedback.

to me it seems that those are quite standard push button, with a top that will accept a standard round or square colored plastic top. Measure the outer dimension of the square, then look at your favorite component provider (or amazon/aliexpress/ebay) E.g. this search on amazon "push button 12mm", I can find this : https://www.amazon.fr/GTIWUNG-Interrupteurs-Bouton-poussoir-dinterrupteurs-Bouton-Poussoir/dp/B08VNB6BX5/ref=sr_1_6?keywords=push+button+12mm&qid=1679603468&sprefix=push+button+12%2Caps%2C123&sr=8-6

Sorry, there is no more with me, and I have no more time. You will have to either build it yourself, or find someone that can do it. The assembly in itself needs basic level in soldering (only through-hole components), the problem for me is more about being able to program a GAL16v8 (one must have a GAL programmer, and depending on the GAL manufacturer, one may have to recompile the source instead of using the provided JED) Thanks for the praise @DarkLord

Hello, Recently mentionned by @DarkLord in several topics, I have recreated the PCB of a serial port upgrade named RSVE. https://github.com/sporniket/atari-st-mod-serial-port-upgrade-rsve The gerbers and schematics are available in the release : https://github.com/sporniket/atari-st-mod-serial-port-upgrade-rsve/releases/tag/v1.0.0 The latest pages of the original thread at exxosforum shows the various attempts to convince BBS Express to works with the accelerated port. The github repository also contains the original archive that include the JED file and its source, to program the GAL16V8. (I also have reformated the original documentation to be nicely viewable on github) : https://github.com/sporniket/atari-st-mod-serial-port-upgrade-rsve/tree/main/reference/rsve

The only thing I regret, is that at that time I did not know enough in computer science to make the most of it. And that the language disk did not provided a compiler with the basic.

Yes the module sold by Exxos is very tiny, as you can see. English Post Office is in a mess, so yes, he closed the webshop for some weeks. Indeed I remember that Exxos states that only old drives use 12V. And I guess that the survival of this 12V rail is due to being "standard connector" (de facto).

Hello. Recently, I experimented with a cheap 15W USB Power delivery compatible phone charger to have 5V with up to 3Amps : https://www.atari-forum.com/viewtopic.php?t=42334 However, for connecting correctly to a SCART TV, one should still have a 12V power rail, hence the use of a little DC-DC converter 5V->12V. Also, I use a floppy emulator instead of a legacy floppy drive, it should help by lightening the load.

The only 3D game I tried playing more than 30 secondes is Epic, a 3D space shooter. The intro is nice, mixes bitmap backdrops with 3d models, and a space-opera-esque MOD soundtrack, to present a settings largely inspired from galactica.

I know that exxos complains a lot about hotmail and hotmail easily and regularly blacklist his domains, so that anyone with a gmail/hotmail address can never ever get the confirmation mail and receipt from his domain. Maybe this is the same problem ?

http://tho-otto.de/keyboards/ that's the closest to what you are looking for, that I am aware of.

It may be a little bit tight, but one may save some space by not supporting the external blitter and the modulator/composite encoder. On the other hand, one could reuse some ideas from Exxos's H5 like a modern RS-232 IC that does not require dedicated voltages converters, and using a single 72-pins SIMM.