Philips CRT TV (chassis L04HE AA) via SCART RGB - vertical sync not locking with

[epzylon]

Hello guys,

I am having a vertical sync issue connecting a PC to a Philips CRT TV via SCART RGB and would appreciate any help from someone with experience with this specific chassis.

HARDWARE
- TV: Philips 25HT5405/01Z, chassis L04HE AA
- GPU: AMD Radeon HD 5450
- Driver: CRT Emudriver 2.0 WDDM v1.20
- Cable: VGA to SCART RGB (Retrocables.es), passive cable, H+V mixed with 2x1kΩ resistors on SCART pin 20, USB powers pin 16 for RGB activation

SYMPTOM
The desktop image is fully visible with correct colors (RGB is working). However, the image rolls continuously vertically without locking. With composite sync disabled the rolling is fast. With composite sync enabled the rolling becomes slow and the image appears stretched/distorted to the right.

WHAT HAS BEEN TRIED
- Monitor presets: Arcade 15.7 kHz, Generic 15.7 kHz, PAL TV 50Hz/625, no difference
- Composite sync: tested enabled and disabled, behavior changes but sync never locks
- EDID emulation: tested enabled (generic_15) and disabled, no difference
- Manual timing adjustments in monitors.ini (vfp, vsync width, vbp), no difference
- TV hotel menu: RGB Priority set to SCART, Installation set to AV1
- TV service menu: VSH OFFSET adjusted from -15 to +15, no effect on SCART input
- Desktop resolution: 640x480 and 320x240, no difference

CURRENT monitors.ini LINE FOR PAL
crt_range0 15625.00-15625.00, 50.00-50.00, 1.500, 4.700, 5.800, 0.064, 0.160, 1.056, 0, 0, 192, 288, 448, 576

CONCLUSION SO FAR
RGB signal is confirmed working. Horizontal frequency is correct at 15.620 kHz (standard VGA monitor rejects the signal as out of range, confirming 15kHz output). The problem is exclusively vertical sync locking.

So, has anyone successfully connected a PC via CRT Emudriver to a Philips chassis L04HE AA through SCART RGB? Is there a specific timing configuration or service menu register in this chassis related to vertical sync processing on the SCART input?

Any help is greatly appreciated.

[makya]

Did you try changing polarities:

example, crt_range0 15625.00-15625.00, 50.00-50.00, 1.500, 4.700, 5.800, 0.064, 0.160, 1.056, 0, 0, 192, 288, 448, 576
-> crt_range0 15625.00-15625.00, 50.00-50.00, 1.500, 4.700, 5.800, 0.064, 0.160, 1.056, 1, 1, 192, 288, 448, 576

Also, some of your photos look fine, TV with stable picture. When does stable picture happen? And when does stable picture happen?

[Zebidee]

- Cable: VGA to SCART RGB (Retrocables.es), passive cable, H+V mixed with 2x1kΩ resistors on SCART pin 20, USB powers pin 16 for RGB activation

The problem is that your H & V sync lines are tied together. This produces what I call "smushy sync", with horizontal pulses going the wrong way *during* the vertical sync pulse, and some other horizontal pulses that should be nearby are completely missing.

Most TVs seem to accommodate this weirdness, but some don't. Some TVs will work fine but show a little zigzag at the top of the screen as the TV's electronics work out where to begin the new frame.

You tried doing composite sync out from CRT_emulator right? The reason why this didn't work is that CRT_EMU, when it produces composite sync, does not switch off the vertical sync pulse. So you're getting csync on VGA pin 13 AND vsync on VGA 14. These then get smushed together in your cable, giving you messy-smushy sync. You have no hope like this.

To solve the issue, you must disconnect the vertical sync input to the cable. As in cut the wire. That way you can run with csync enabled via CRT_EMU, which will come out from VGA pin 13 to SCART pin 20.

If you want to be able to restore the vertical sync later then you could solder on some connectors - I've done it before using wires with male/female dupont connectors (like what people use with Arduinos and such). I can dig out some pics if you are curious.

If it still doesn't work then try using a lower value resistor (e.g. 470R) on the H-sync line. 1K is a little on the high side, at least for the h-sync.

I hope this helps. Sorry it took my so long to see and respond to your post. I've had my head buried in GreenAntz development