64kib

07/19/2017

FO 08:14 PM EclaireXL Feature #55 (New): Replace main CPU

I really find the stack based zpu annoying to debug. Also as its setup the rom is full.
Consider replacing with something newer, also with gcc support, such as https://github.com/SpinalHDL/VexRiscv. foft

07/17/2017

FO 08:21 PM EclaireXL Developer: RE: Relocate that cartridge slot - Cartridge slot extender available to order.

Do you know how to use Eagle? The free version is good enough and its not that hard. You could load the existing sub-board as a base schematic. Then order somewhere like this: http://dirtypcbs.com/store/pcbs foft

FO 08:11 PM EclaireXL 917k's setup!

I'm sure you've already seen Steve's great setup, but if not go and see here. Very nice work:-)
http://atariage.com/forums/topic/267845-my-eclairexl-a-salute-to-the-atari-400-my-first-atari-computer/
I'm still working away on the cor... foft

07/15/2017

FO 09:47 PM EclaireXL Bug #25: F10 Hard Reset Ignore inserted cartridge (Core v7)

This is the last thing remaining for V15. In order to do it (simply) I decided to allow off PBI access from turbo mode and zpu. That seems to work now, except its failing timing. I think I need to plumb the internal freezer in differentl... foft

FO 09:44 PM EclaireXL Bug #25 (In Progress): F10 Hard Reset Ignore inserted cartridge (Core v7)

foft

07/10/2017

FO 09:35 PM EclaireXL Developer: RE: USB AB Connector

By mistake, the pin should be removed. foft

07/09/2017

FO 01:25 PM EclaireXL Feature #24: A board with Atari SOUL!!!! (ROM in block ram support)

I'm using block ram in the FPGA for the OS ROM and BASIC. It can be read in 2 cycles and written to in 1 cycle. SDRAM takes about 5-6 iirc. So in turbo mode, with no cpu cache, this makes a huge difference in speed. foft

07/08/2017

FO 08:01 AM EclaireXL Developer: RE: Atari 400-style key caps just back from WASD!

I need to do something about the firmware soon, there are about 4 bytes free! Of course we have plenty of resources but it needs some work to map more ram or further restructure the support CPU and firmware. More buttons are after that... foft

FO 07:58 AM EclaireXL Developer: RE: On Off Controller by Maxim

So we'd have this instead of the toggle switch? Then a tps63002 for the stable 5V?
Guess it would be good to have main button on/off, though I do like the toggle:) foft

07/07/2017

FO 09:26 PM EclaireXL Feature #24: A board with Atari SOUL!!!! (ROM in block ram support)

Also of course nice and fast vs uncached sdram...
sysinfo fp test from 6x->20x :-) I probably need a cache to get this closer to 30-40x, but that will take some work. foft

FO 09:13 PM EclaireXL Feature #2: PBI support

Added antic refresh cycles foft

07/06/2017

FO 09:28 PM EclaireXL Feature #51: Debug port

I have a first cut of this building. This will be part of the v15 core.
Next I need to build the capture software to stream this into the PC. Then some post-analysis software, probably a hacked up emulator. foft

07/05/2017

FO 09:41 PM EclaireXL Bug #49 (Closed): CORE13 - NTSC/PAL switching

foft

FO 09:40 PM EclaireXL Bug #49: CORE13 - NTSC/PAL switching

Fixed, will be in v15 when I release it. foft

07/04/2017

FO 09:31 PM EclaireXL Bug #49: CORE13 - NTSC/PAL switching

Trying to fix this one, but its nasty. I need more brain cycles to fix it... foft

FO 09:29 PM EclaireXL Feature #14: Svideo core for first prototype

Hmm, just reading that IRE is _relative_ so that might be why increasing voltage didn't make anything brighter!!
https://en.wikipedia.org/wiki/IRE_(unit)
So I wonder if I could have a 0V-0.5V signal that uses the correct relative s... foft

FO 07:25 PM EclaireXL Developer: RE: Atari 400-style key caps just back from WASD!

Backlit too. Your one looks far better than the one on Amazon! foft

FO 07:02 AM EclaireXL Developer: RE: Atari 400-style key caps just back from WASD!

Cool! That looks amazing:)
What is the keyboard that you fitted the keycaps too? Seems to match the 800 case. foft

07/03/2017

FO 07:10 AM EclaireXL Wiki edit: Wiki (#26)

foft

07/02/2017

FO 10:50 PM EclaireXL Feature #14: Svideo core for first prototype

For anyone with composite/svideo setup. Please can you tell me what you think of svideo_gtia6.sof vs the previous version.
This is generated more the 'atari way' - i.e. off hue/brightness with phase shifts, rather than being based on ... foft

FO 11:42 AM EclaireXL Feature #14: Svideo core for first prototype

I mean svideo and composite, it's the same thing pretty much.
I've got the gtia style one running pretty well for ntsc now. Its interesting to implement if nothing else:) foft

FO 01:10 PM EclaireXL Bug #54: GTIA issue when Turbo > 4X

Yeah, this kind of test program is very helpful. Thanks. foft

FO 11:39 AM EclaireXL Developer: RE: new video uploaded

HDMI, dvi and vga mode are 50Hz (HDMI is picky) other modes are 49.86Hz like the Atari. Nir tell me it's still faster though so not sure why!
For ntsc it's 59.94Hz and 59.92Hz iirc. foft

07/01/2017

FO 05:05 PM EclaireXL Feature #14: Svideo core for first prototype

That works, kind of! Basic screen and star wars shields look the correct colours, but I have no red. Also very grainy and svideo is a single colour?! foft

FO 12:59 PM EclaireXL Feature #14: Svideo core for first prototype

Writing an 'atari-style' implementation instead of going via RGB. Fixed saturation, simple phase shift for colour. foft

FO 07:10 AM EclaireXL Feature #14: Svideo core for first prototype

Interesting...
http://atariage.com/forums/topic/29621-atari-video-circuits-experiment/
So fixed saturation (except gray), just phase shifted for the cols. Then add luma. Might try that rather than generic rgb component. foft

FO 04:25 PM EclaireXL Developer: RE: How to check core version?

I guess I can include svn revision, though will need to find some bytes in the firmware:-) & commit code first! foft

FO 03:59 PM EclaireXL Feature #53 (Closed): Add version number to settings

Add version number to settings foft

06/30/2017

FO 10:15 PM EclaireXL Bug #52: Atari Control Picture

I checked an older core in case I introduced it with the antic timing changes for pbi. Was bad then, so unrelated.
This is a nice static picture to debug in sim or signaltap. I like this kind of test case:-) foft

FO 10:10 PM EclaireXL Feature #14: Svideo core for first prototype

Added a poke 712,15 for comparison of max values. Interesting how the amplitude for basic 'blue' is so much higher yet the peak amplitude is comparable...
Atari:
!composite_atari_max.png!
Eclaire:
!composite_eclaire_max.png! foft

FO 09:54 PM EclaireXL Feature #14: Svideo core for first prototype

I mean see how the 'white' on ready already takes most of the range, without trying to increase it. foft

FO 09:54 PM EclaireXL Feature #14: Svideo core for first prototype

Atari
!composite_atari_basic.png!
Eclaire
!composite_eclaire_basic.png!
We have a range of 0-1v on the DAC. 0-0.3V sync and 0.3V-1.0V is set by changing the dac level. So trouble is its not really enough. Might still need to chan... foft

FO 09:50 PM EclaireXL Feature #14: Svideo core for first prototype

Added traces of Atari basic from the scope, to see the voltage level differences.
Eclaire is driving my monitor, Atari is through a 66ohm resistor (little low, so voltage is suppressed a little).
Still, a stark difference! foft

06/29/2017

FO 08:59 PM EclaireXL Bug #49: CORE13 - NTSC/PAL switching

I think I've identified the problem. If the zpu happens to exit the menu at the end of an 'original' cycle the pbi logic can block the response from a memory access. Now to think about how to implement this in a better way... foft

FO 08:05 PM EclaireXL Developer: RE: new video uploaded

Thanks Nir, great video as always:) foft

FO 08:05 PM EclaireXL Developer: RE: Holy shit - Joe Decuir has en Eclaire

Yes it's true, Joe has one and will be helping out as time allows. foft

06/27/2017

FO 07:54 PM EclaireXL No news

No news, I've been ill but am almost better!
Is anyone still alive here?
On an unrelated note found this article on how FPGAs work and thought it might be of interest: http://blog.notdot.net/2012/10/Build-your-own-FPGA
foft

06/26/2017

FO 07:33 PM EclaireXL Wiki edit: Wiki (#25)

foft

06/23/2017

FO 07:27 AM EclaireXL Feature #11: Non-uk keyboard support (custom keyboard mapping)

It's written in c. The Atari core is built with a DMA port and the ability to freeze the 6502. Outside that there is another CPU (the zpu) that draws the menu, handles USB, se card, drive emulation etc. It has quite a lot of custom hardw... foft

06/22/2017

FO 09:12 PM EclaireXL Feature #11: Non-uk keyboard support (custom keyboard mapping)

Yeah, that should work. You just described a multiplexor btw.
Got guests this weekend, so will do the plumbing next week. foft