ZZ9000 Video interference in Scan Doubled modes

  • Amiga model: A4000TX
  • 680x0 CPU: 68060 (A3660 @ 50 MHz)
  • RAM Configuration: 2 MB Chip, 16 MB MB Fast, 256 MB ZZ9000
  • Kickstart, AmigaOS Versions: 3.2
  • ZZ9000 Firmware version: 1.9 (same on 1.8)
  • ZZ9000 Driver version: 1.8
  • Monitor model: Eizo Flexscan S2100
  • Other Zorro cards: NIL

I noticed this after installing an A3660 card. Scan doubled modes exhibit video interference via the ZZ9000. Note RTG modes are fine, and using the 15KHz output from the A4000TX direct to a second monitor is also fine.

Based on this I’m thinking interference from the Video connector or ribbon cable???

When using the built-in 030 @ 25MHz I didn’t see this behaviour.

Take a look at this YT clip. The interference can be seen from 10 sec into the clip.

Just an update on this looks like a can consistently repro this now. The issue appears when USB is in use. So if mount a USB drive, I’m guessing when I run sysinfo it might initially scan all devices, causing the interference.

But when run the disk test it will consistently cause inteference on speed testing the USB drive. It’s hard to see in the video but much much more visible to the naked eye.

See video:

Now I know what is causing the issue I can live with it, but any suggestions to quiet down the USB port would be appreciated.

Any response from MNT?

This is going to sound a little strange but if you drop to 640x512x8 bit resolution do you still get the same effects?

Hi Steve,

I tried both 640x512x8 (RTG) and PAL Interlaced (Flicker fixed) and it seemed fine.

I’ll do some more testing update.