ao486 Config for a Plain Old CRT TV

[martini2]

Hello,
i have my IO Board XL v6.1 connected to a simple crt tv with a 'VGA to RGB Scart Cable' cable from ultimatemister.com and mister, the consoles and arcade cores run fine on it out of the box. Unfortunately i can not get the ao486 core to display a clear picture on it. There is also no sound. Not through the 3,5 audio jack nor through mt32-pi (the bars on the display are moving when there should be sound laying). Other cores play sound fine.

Is there any info on possible settings for this core or a solution to this sync? problem.

CRT TV AO486 core_t.jpg (69.11 KiB) Viewed 51244 times

my mister.ini

Code: Select all

[MiSTer]
key_menu_as_rgui=0     ; set to 1 to make the MENU key map to RGUI in Minimig (e.g. for Right Amiga)
forced_scandoubler=0   ; set to 1 to run scandoubler on VGA output always (depends on core).
ypbpr=0                ; set to 1 for YPbPr on VGA output.
composite_sync=0       ; set to 1 for composite sync on HSync signal of VGA output.
vga_scaler=0           ; set to 1 to connect VGA to scaler output.
hdmi_audio_96k=0       ; set to 1 for 96khz/16bit HDMI audio (48khz/16bit otherwise)
keyrah_mode=0x18d80002 ; VIDPID of keyrah for special code translation (0x23418037 for Arduino Micro)
vscale_mode=0          ; 0 - scale to fit the screen height.
                       ; 1 - use integer scale only.
                       ; 2 - use 0.5 steps of scale.
                       ; 3 - use 0.25 steps of scale.
vscale_border=0        ; set vertical border for TVs cutting the upper/bottom parts of screen (1-399)
;bootscreen=0          ; uncomment to disable boot screen of some cores like Minimig. 
;mouse_throttle=10     ; 1-100 mouse speed divider. Useful for very sensitive mice
rbf_hide_datecode=0    ; 1 - hides datecodes from rbf file names. Press F2 for quick temporary toggle
menu_pal=0             ; 1 - PAL mode for menu core
hdmi_limited=0         ; 1 - use limited (16..235) color range over HDMI
                       ; 2 - use limited (16..255) color range over HDMI, for VGA converters.
direct_video=0         ; 1 - enable core video timing over HDMI, use only with VGA converters.
fb_size=0              ; 0 - automatic, 1 - full size, 2 - 1/2 of resolution, 4 - 1/4 of resolution.
fb_terminal=1          ; 1 - enabled (default), 0 - disabled
osd_timeout=180         ; 5-3600 timeout (in seconds) for OSD to disappear in Menu core. 30 seconds if not set.
                       ; Background picture will get darker after double timeout
osd_rotate=0           ; Display OSD menu rotated,  0 - no rotation, 1 - rotate right (+90°), 2 - rotate left (-90°)                  

; 1 - enables the recent file loaded/mounted.
; WARNING: This option will enable write to SD card on every load/mount which may wear the SD card after many writes to the same place
;          There is also higher chance to corrupt the File System if MiSTer will be reset or powered off while writing.
recents=0

; lastcore - Autoboot the last loaded core (corename autosaved in CONFIG/lastcore.dat) first found on the SD/USB
; lastexactcore - Autoboot the last loaded exact core (corename_yyyymmdd.rbf autosaved in CONFIG/lastcore.dat) first found on the SD/USB
; corename - Autoboot first corename_*.rbf found on the SD/USB
; corename_yyyymmdd.rbf - Autoboot first corename_yyyymmdd.rbf found on the SD/USB
;bootcore=lastcore    ; uncomment to autoboot a core, as the last loaded core.
bootcore_timeout=10  ; 10-30 timeout before autoboot, comment for autoboot without timeout.

; Option to load the custom font. Format is plain bitmap 8x8.
; Supported sizes of font:
;   768 bytes - chars 32-127 (only alpha + numeric)
;  1024 bytes - chars 0-127
;  1136 bytes - chars 0-141
;  up to 2048 - only chars 0-141 will be used.
; if first 32 chars are empty (for sizes 1024 bytes and more) then they are skipped.
font=font/myfont.pf

; USER button emulation by keybaord. Usually it's reset button.
; 0 - lctrl+lalt+ralt (lctrl+lgui+rgui on keyrah)
; 1 - lctrl+lgui+rgui
; 2 - lctrl+lalt+del
; 3 - same as 0 (lctrl+lalt+ralt on keyrah)
reset_combo=0

dvi_mode=0             ; set to 1 for DVI mode. Audio won't be transmitted through HDMI in DVI mode.

; 0 - 1280x720@60
; 1 - 1024x768@60
; 2 - 720x480@60
; 3 - 720x576@50
; 4 - 1280x1024@60
; 5 - 800x600@60
; 6 - 640x480@60
; 7 - 1280x720@50
; 8 - 1920x1080@60
; 9 - 1920x1080@50
;10 - 1366x768@60
;11 - 1024x600@60
;12 - 1920x1440@60
;13 - 2048x1536@60
;
; custom mode: hact,hfp,hs,hbp,vact,vfp,vs,vbp,Fpix_in_KHz
;   video_mode=1280,110,40,220,720,5,5,20,74250
video_mode=8

; set to 1-10 (seconds) to display video info on startup/change
video_info=10

; Set to 1 for automatic HDMI VSync rate adjust to match original VSync.
; Set to 2 for low latency mode (single buffer).
; This option makes video butter smooth like on original emulated system.
; Adjusting is done by changing pixel clock. Not every display supports variable pixel clock.
; For proper adjusting and to reduce possible out of range pixel clock, use 60Hz HDMI video
; modes as a base even for 50Hz systems. 
vsync_adjust=2

composite_sync = 1

; If you monitor doesn't support either very low (NTSC monitors may not support PAL) or 
; very high (PAL monitors may not support NTSC) then you can set refresh_min and/or refresh_max
; parameters, so vsync_adjust won't be applied for refreshes outside specified.
; These parameters are valid only when vsync_adjust is non-zero.
refresh_min=0
refresh_max=0

; These parameters have the same format as video_mode.
; You need to supply both PAL and NTSC modes if you want vsync_adjust to switch between
; predefined modes as a base. This will reduce the range of pixel clock.
video_mode_ntsc=8
video_mode_pal=9

; 1-10 (seconds) to display controller's button map upon first time key press
; 0 - disable
controller_info=6
scandoubler_disable=1

; JammaSD/J-PAC/I-PAC keys to joysticks translation
; You have to provide correct VID and PID of your input device
; Examples: Legacy J-PAC with Mini-USB or USB capable I-PAC with PS/2 connectors VID=0xD209/PID=0x0301
; USB Capable J-PAC with only PS/2 connectors VID=0x04B4/PID=0x0101
; JammaSD: VID=0x04D8/PID=0xF3AD
jamma_vid=0x04D8
jamma_pid=0xF3AD

; Speeds in sniper/non-sniper modes of mouse emulation by joystick 
; 0 - (default) - faster move in non-sniper mode, slower move in sniper mode.
; 1 - movement speeds are swapped.
sniper_mode=0

; Uncomment following option if you don't want to see a second line for long file names in listing.
;browse_expand=0

; 0 - disable MiSTer logo in Menu core
logo=1

[hiddenbyleaves]

Add this to your .ini

[ao486]
video_mode=640,8,58,78,240,1,3,18,12324
vga_scaler=1
vsync_adjust=2
vscale_mode=0

[hiddenbyleaves]

This should give you a stable picture. I'm not sure about the sound.

[RascalUK]

Not stable for me. Same kinda image as above that martini2 gets. I get to see the ao486 logo but after that...nope Ah well.

[MiSTer_Kirk]

This works on my Sony CRT

[ao486]
vga_scaler=0
video_mode=640,6,56,66,224,14,8,18,12000

224 vertical res is a bit low, and causes some text in games a little hard to read. But it does work for me.

[lister_of_smeg]

This may not be the problem, but I notice you have both composite_sync=0 and composite_sync=1 on two separate lines in your MiSTer.ini.

[akeley]

I've tried both these configs. The image is stable (not in all games though), but the scaling is off, not just in DOS. Perhaps, with a better modeline...

[RascalUK]

This works on my Sony CRT

[ao486]
vga_scaler=0
video_mode=640,6,56,66,224,14,8,18,12000

224 vertical res is a bit low, and causes some text in games a little hard to read. But it does work for me.

Yay, this works on my 14" Panasonic. Thanks!!

Menu etc is difficult to read but text in a couple of games I tried was fine.

[RascalUK]

Actually, everything is squashed into the middle third of the screen, but at least I get a picture now. Progress.

Update...oops had it on original aspect. Change to full screen and it's pretty much sorted. Just lose some text off the sides of the menu.

[martini2]

Thank you. I have a stable picture now, but it is hard to read. On some games content is missing. There are not enough lines.
How do i calculate a video_mode with more lines? I also don't understand why mode 3 (720x576@50) won't work on this pal tv? Is this not the native resolution?

CRT TV AO486 core_240_t.jpg (83.59 KiB) Viewed 50897 times

There is also no picture on a monitor connected through hdmi.
Is it not possible to have a picture on a monitor and the crt tv at the same time?

[MiSTer_Kirk]

Actually, everything is squashed into the middle third of the screen, but at least I get a picture now. Progress.

Update...oops had it on original aspect. Change to full screen and it's pretty much sorted. Just lose some text off the sides of the menu.

Excellent. If you find any better modelines then please post them here. I have tried and tried so many, but only this one worked.
I do think that, if we can "Tweak" the settings, maybe lower the refresh so it's slightly flickery - I would take a slightly flickery screen, but with more readable text. I will keep experimenting.

[FoxbatStargazer]

640x240 is too low a resolution for HDMI, its below spec. You need to set the width to 1920 or even higher to have a chance, though I think that might break the scaler too. (This is incidentally how direct_video works with most cores, with 28xx by 240 resolutions. Don't think ao486 is set up with a good direct_video for CRT TVs though.)

I would also make sure that vscale is set to 1 when using the scaler, otherwise the 200 tall original DOS stuff is going to be expanded to 240 tall in an ugly way.

[RascalUK]

Excellent. If you find any better modelines then please post them here. I have tried and tried so many, but only this one worked.
I do think that, if we can "Tweak" the settings, maybe lower the refresh so it's slightly flickery - I would take a slightly flickery screen, but with more readable text. I will keep experimenting.

There's also definite banding on my image too with this modeline, which doesn't appear in any other cores so I know it's not the TV. I tried tweaking a little but lurched from seeing no difference to making it not work again

xO5ghfC.jpg (97.36 KiB) Viewed 50627 times

Ignore the different blue at the top, that's the camera, but you can see the horizontal lines throughout. No visible flicker, just there.

[Caldor]

I should look into what my MiSTer settings ended up being. I got it fully working with a CRT monitor, but it was mainly the Minimig core I tested.

[rcade]

As mentioned, VGA is not for 15KHz, you will either be missing info or it will look terrible.

The only use for 15KHz display would be a monochrome text output, or possibly a partial CGA implementation. Anything else and you are rigging something for which it was never intended. Use VGA or HDMI.

[akeley]

Displaying VGA games on 15khz TVs actually makes a lot of sense, much more than the other way around. This way games can benefit from TVs' natural antialiasing coming from much more articulated shadowmask/scaline combo, plus more vivid colours, glow, and other consumer-type CRT intrinsic qualities.

I do it already on my PC with crtemudriver, there's nothing "missing" and it looks great, similar examples here: https://www.vogons.org/viewtopic.php?f=31&t=75774

MiSTer's ao486 seems really close to that possibility now as well, as witnessed by some of the attempts in this thread, and also here. Hopefully one day it will be possible for at least for standard (320x200/240) VGA games in a 1:1 fashion.

[ash2fpga]

There are a fair number of games made with "CGA Composite" support that could make 15khz output useful (albeit with a composite conversion).

Moby Games has a list:
https://www.mobygames.com/attribute/she ... Id,29/p,4/

I found the Moby Games link from this blog post:
http://pcretrogames.blogspot.com/2010/1 ... -mode.html

[FoxbatStargazer]

The thing that can suck with a TV is overscan. PCs assumed your monitors didn't have any, so there may be vital information in the corners that gets lost in consumer TVs. I would use a 240/244p mode to provide some space for the 200p games to be centered in. Not sure how you would go about creating a border on the left/right though.

[lu_source]

Is it possible to disable the analog output over the IO board.

I have my MiSTer FPGA connected to both a CRT and an HDMI monitor. When I run the ao486 core, I would like the output to be sent to only the HDMI port and disable the analog port altogether.

Any help would be appreciated.

[flynnsbit]

The thing that can suck with a TV is overscan. PCs assumed your monitors didn't have any, so there may be vital information in the corners that gets lost in consumer TVs. I would use a 240/244p mode to provide some space for the 200p games to be centered in. Not sure how you would go about creating a border on the left/right though.

I didn't publish this video publicly because of the terrible audio capture from the MiSTer. This was before I switched to toslink. Point is, this is a CRT TV and you can get pretty close with a combination of vscale_border= and a custom resolution/AR. Again, the audio in this is horrendous but the point is to show the video of the ao486 core running on a regular crt.

https://www.youtube.com/watch?v=W0ScMbmXMG8 (switch to 1080p on YT)

[flynnsbit]

Is it possible to disable the analog output over the IO board.

I have my MiSTer FPGA connected to both a CRT and an HDMI monitor. When I run the ao486 core, I would like the output to be sent to only the HDMI port and disable the analog port altogether.

Any help would be appreciated.

you have to use the scaler when using ao486.

[Schnookums]

Keeping an eye on this thread, as so far nothing I've done works, I might get a clear picture for half a second before it starts to roll the image. Using a Sony Trinitron kv-13fs100

[Caldor]

I thought I shared my configuration in this thread already. Oh, seems I shared it in the wrong thread.

Oh well, here it is. For me this works quite well as it works on my CRT monitor for both the Amiga Minimig core and the AO486 core in all the resolutions I have tried so far. It allows for an LCD monitor to be connected to the HDMI at the same time as you use a CRT on the IO boards VGA port. It should not need the HDMI though, as it supports the overlay, running special scripts and so on, on the CRT.

Not sure if it works with 15khz screens though.

[RascalUK]

Yeah, that didn't work on my 15khz unfortunately.

[Caldor]

Yeah, that didn't work on my 15khz unfortunately.

But isn't the problem here that the core does not support 15khz? Afaik, the scandoubler option is MiSTer specific because Amiga hardware used 15khz monitors. That is not the case with PCs though, or at least I do not think it is.

So... instead it seems to need to do the opposite of what a scandoubler does? So, pretty much throwing away several frames. I am not sure, but I think I have seen several threads about 15khz support.

[Caldor]

I found another thread that might be relevant here. It seems to call it "underscanning"

what might have worked there was:
"Instead of vga_scaler=1, you can also try vscale_mode=1

vga_scaler=1 gave me big black lines on most resolutions.
with vscale_mode=1 all resolutions seem fine."
viewtopic.php?f=13&t=1448&p=23560&hilit=15hz#p23560

[lu_source]

Is it possible to disable the analog output over the IO board.

I have my MiSTer FPGA connected to both a CRT and an HDMI monitor. When I run the ao486 core, I would like the output to be sent to only the HDMI port and disable the analog port altogether.

Any help would be appreciated.

you have to use the scaler when using ao486.

This doesn't help in my situation. Turning on the scaler makes things worse. I have the MiSTer connected through composite and I do not want any signal going to my CRT TV. I just want HDMI output when I load the ao486 core. Really trying to avoid unplugging the composite cable when I'm using the ao486 core.

[RascalUK]

Out of interest, why do you want to disable the analogue?

[FoxbatStargazer]

I don't know of any option that outright disables either of the video outputs. You need an external switch if you don't want to simply shut your TV off or change inputs.

[akeley]

I found another thread that might be relevant here. It seems to call it "underscanning"

what might have worked there was:
"Instead of vga_scaler=1, you can also try vscale_mode=1

vga_scaler=1 gave me big black lines on most resolutions.
with vscale_mode=1 all resolutions seem fine."
viewtopic.php?f=13&t=1448&p=23560&hilit=15hz#p23560

I have linked to this thread on the previous page. With settings from there the scaling itself looks fine on my consumer TV, but image goes into overscan horizontally. Maybe on PVM it can be remedied, hence matsu's good result. Perhaps with better modeline it could work on normal TVs too.