Project

General

Profile

Activity

From 05/31/2018 to 06/29/2018

06/21/2018

FO 09:44 PM Bug #67: Pokey two tone timing problem
I found if I pokey 53775,11+128 on the Atari then it matches the Eclaire output. Unfortunately forcing the serious output on eclaire to 1 or 0 does not change anything. Still its something to go on! foft

06/20/2018

FO 10:03 PM Bug #67: Pokey two tone timing problem
So, errr identical then! Going to have to think about this one...
B is Atari, A is EclaireXL.
!http://www.64kib.com/redmine/attachments/download/82/Screenshot%20from%202018-06-20%2023-02-19.png!
foft
FO 09:57 PM Bug #67: Pokey two tone timing problem
Nope, seems to be some interaction with the noise filtering. I wonder if the delay also needs applying to the pulse from the timer, that then hits the noise filter. foft
FO 09:27 PM Bug #67: Pokey two tone timing problem
A 2 cycle delay on the reset fixes both the 4 cycle and the 9 cycle case.
Now to check this specific example!
foft

06/19/2018

FO 09:55 PM Bug #67: Pokey two tone timing problem
I was concerned that my clocks were off at first since I was running in VGA mode, but that changes vsync slightly (50Hz vs 4.86Hz) which of course also impacts audio frequency:-) Debugging in RGB mode gives a perfect match. foft
FO 09:54 PM Bug #67: Pokey two tone timing problem
Been measuring cases on the scope...
Confirmed the extra cycle delays described in that forum post on my 600XL. Confirmed missing on the EclaireXL implementation.
foft

06/14/2018

FO 08:35 PM Bug #67: Pokey two tone timing problem
Related post: http://atariage.com/forums/topic/118448-implementation-of-pokey-2-tone-filter-in-emulation/page-3#entry1449990 foft

06/11/2018

FO 09:09 PM Feature #65: Implement ATA to SPI bridge
What is used in set features?
0xef set features, then set feature 1 + lba mode?
Think this can probably be ignored.
foft
FO 09:04 PM Feature #65: Implement ATA to SPI bridge
Identify:0xec
0->SCNT,SNUM,CYLL,CYLH
0xa0->HEAD
0xec >STAT
read stat -> if 0 then does not exist! Then wait for BSY to clear and RDQ to set.
read data -> 512 bytes
See above for the interesting bytes from this.
foft
FO 08:53 PM Feature #65: Implement ATA to SPI bridge
https://wiki.osdev.org/ATA_PIO_Mode
Probably want at least DRQ(3/ 1=ready), RDY(6 /1=good) and BSY(7/ 0=not busy) in the status reg
foft
FO 08:40 PM Feature #65: Implement ATA to SPI bridge
Some links..
https://www.pjrc.com/tech/8051/ide/wesley.html#idereg
http://atariage.com/forums/topic/279232-fujiconvert-01/page-3
Simple read seems to be:
sector address-> 4 lba regs with $e0 in high part
scnt-> 1
stat-> cmd
data...
foft
SA 08:32 PM Feature #71: Add support for user firmware updates
foft wrote:
> Add support to load new firmware from sd card. Then it can be applied immediately for testing or flashed.
> ...
:-)
sadosp
FO 08:24 PM Feature #71 (New): Add support for user firmware updates
Add support to load new firmware from sd card. Then it can be applied immediately for testing or flashed.
I'd like this to make it easier to build/test new firmware.
foft

06/10/2018

SA 09:00 PM Feature #70: Add hotkeys for video mode selection
foft wrote:
> I think its on the right windows key, checking...
I have to see keyboard with two windows keys many years now. Please could you add also this to the standard left window key???
sadosp
FO 08:52 PM Feature #70: Add hotkeys for video mode selection
I think its on the right windows key, checking... foft
SA 08:35 PM Feature #70: Add hotkeys for video mode selection
foft wrote:
> + Added 1,2,3,4 for profile switch + load
Marvelous!
So many keys, but still wait for the day to add the fire key on keyboard!
sadosp
FO 08:19 PM Feature #70: Add hotkeys for video mode selection
+ Added 1,2,3,4 for profile switch + load foft
FO 08:12 PM Feature #70 (Closed): Add hotkeys for video mode selection
Will release in v24 foft
FO 08:12 PM Feature #70: Add hotkeys for video mode selection
Added something simple...
Press F11 to go to menu.
Then press:
P: PAL
N: NTSC
R: RGB
A: SCANDOUBLE
D: DVI
H: HDMI
V: VGA
S: SVIDEO
C: COMPOSITE
Z: Toggle composite sync
X: Toggle scanlines
foft
FO 08:10 PM Feature #70 (Closed): Add hotkeys for video mode selection
Been meaning to add a simple way to switch mode from keyboard. foft
FO 08:14 PM Core v24
Very small change since I've realized how annoying the video mode selection is (i.e. find sd card, copy on settings...)
Added some hotkeys. To use them go to the F11 menu and then press:
P: PAL
N: NTSC
R: RGB
A: SCANDOUBLE
D: DVI...
foft

06/07/2018

FO 06:48 AM Bug #64: Pokey pdm timing incorrect
Anyway v23 sounds nice for pdm, reliably. foft
FO 06:47 AM Bug #64: Pokey pdm timing incorrect
The issue was that the write to stimer was now exactly on the enable cycle. I modified the latch delay line to support this. Fundamentally though, this isn’t meant to happen, so perhaps an issue with the pbi implementation is causing the... foft
FO 06:45 AM Bug #69: Some TVs confused by hdmi audio
See video for example
https://photos.app.goo.gl/c3VMPp0XY7nIaJBG3
Not much to go on. Perhaps the clock regen packets are slightly out of spec or perhaps it does not like the sample rate.
foft
FO 06:43 AM Bug #69 (New): Some TVs confused by hdmi audio
foft
FO 06:42 AM Bug #6 (Closed): HDMI audio poor quality
foft

06/06/2018

FO 06:28 PM Core v23
A small update, mostly for farb to test HDMI audio
* Add low pass audio filter, massively reduces HDMI audio high frequency aliasing
* Fix an stimer write problem introduced in v22 (more work to do here)
foft

06/05/2018

FO 10:07 PM Bug #64: Pokey pdm timing incorrect
Aha, got it... foft
FO 09:58 PM Bug #64: Pokey pdm timing incorrect
Problem with stimer?? foft
FO 09:09 PM Bug #64 (In Progress): Pokey pdm timing incorrect
Reopening, inconsistent timing in calibrate foft
FO 09:07 PM Bug #31 (Closed): HDMI Audio generate high pitch noise (Core 8)
foft
FO 09:07 PM Bug #31: HDMI Audio generate high pitch noise (Core 8)
Added a low pass filter and this is gone, to be released in v23. foft
FO 09:07 PM Bug #6: HDMI audio poor quality
Wired this up and sounding much better.
Unfortunately @farb seems to have completely different symptoms! https://photos.app.goo.gl/c3VMPp0XY7nIaJBG3. Here jumpman is sounding good, even before the filter.
foft

06/04/2018

FO 10:00 PM Bug #6: HDMI audio poor quality
Could look into FIR and IIR filters, but to be honest this seems very lightweight and to work well. Will implement and see what it sounds like! foft
FO 09:58 PM Bug #6: HDMI audio poor quality
Trying out various options in Octave.
sample = current method (just take the current value), flat line at top!
mean = mean of last n samples (which did not meet timing due to expensive division)
meanfpga = mean of last 32 samples (e...
foft
FO 09:15 PM Feature #68: Implement stock Atari 800 mode
I agree, not to mention that 4th joystick port's poor fire button. I actually built most of this for the mist a while back. foft

06/03/2018

FO 08:35 PM Bug #6: HDMI audio poor quality
Investigating resampling high frequencies to 48KHz with some plots in Octave. The average that I removed wasn't a bad simple low pass filter (though didn't meet timing...). The way I did it (just sample) sucks, quite frankly. Any high fr... foft
FA 11:21 AM Feature #68 (Closed): Implement stock Atari 800 mode
It would be great to have the option of using NTSC, OS-B and 48K to reflect an unmodified Atari 800. There are also older Electronic Arts titles (Archon, M.U.L.E., One on One) that do protection checks for custom O.S. code and those fail... Farb

06/02/2018

FO 10:15 PM Bug #31: HDMI Audio generate high pitch noise (Core 8)
HDMI audio is sounding better now in general (signed/unsigned). This high pitched noise is still heard in some cases though, so it needs further investigation. foft
FO 10:06 PM Core v22
Received my board today.
I tried to understand the flash chip problems. All I found so far is that it has a 64KB sector size, so I've added detection by id so that we can have one v2 core for both different flash chips.
* Detect fl...
foft
FO 08:27 PM Bug #66: Odd flash behaviour on new boards
Flashing a new PDM is very clear that the board is erasing in 64KB blocks. That does not explain the core corruption on saving settings though.
I'll set the block size to 64KB when spotting this ID and see how it does!
foft
FO 08:01 PM Bug #6: HDMI audio poor quality
The biggest issue with this appears to be that I need to send signed samples. Changed that and its sounding much better. foft

06/01/2018

AD 10:46 AM Bug #64 (Closed): Pokey pdm timing incorrect
Seems to run fine, Acid now passes again as far as I can tell. admin
FO 08:24 AM Bug #64: Pokey pdm timing incorrect
Been checking on the scope. The one cycle delay looks correct.
Some jitter issues due to when I activate pokey. I was doing so on the memory access completion, but this really varies too much when accessing SDRAM and block RAM. So I've ...
foft
AD 10:42 AM Bug #67 (Resolved): Pokey two tone timing problem
An old bug.. See http://atariage.com/forums/topic/228527-pokey-emulation/page-3#entry3060595
10 P=53760
20 POKE P+8,64
30 POKE P+1,10+32
31 POKE 53775,11
40 POKE P,20
50 GOTO 50
high pitched, low pitched on real Atari
admin
 

Also available in: Atom