[haiku-development] EDID Problem

Attached are two dumps of EDID information from the same monitor (Samsung 710N LCD monitor). The EDID info was obtained in both cases by calling the ddc2_read_edid1() function in the Common Accelerant, and the dump was obtained by using the edid_dump() function. The good info was obtained with a Savage4 chip and the bad info was obtained with a ProSavage DDR-K chip. The bad info looks like most of the values in the data consists of 0xff values; however, ddc2_read_edid1() returns B_OK in both cases. I'm wondering if ddc2_read_edid1() can detect if the data is bad by looking at some of the data values.
I have been unable to determine why the ProSavage DDR-K chip returns garbage, and am not inclined to spend any more time investigating this problem. Thus, I set up the S3 driver to look at the EDID version in the EDID data, and if it is 0xff, it assumes that the data is garbage and the data is then ignored. 

Best regards,
Gerald

Vendor: SAM
Product ID: 286
Serial #: 1296707895
Produced in week/year: 39/2004
EDID version: 1.3
Type: Analog
Size: 34 cm x 27 cm
Gamma=2.200
White (X,Y)=(0.313,0.329)
Supported Future Video Modes:
1280x1024@60Hz (id=32897)
1152x864@75Hz (id=20337)
Supported VESA Video Modes:
720x400@70
640x480@60
640x480x67
640x480x72
640x480x75
800x600@56
800x600@60
800x600@72
800x600@75
832x624@75
1024x768@60
1024x768@70
1024x768@75
1280x1024@75
1152x870@75
Additional Video Mode:
clock=108.000000 MHz
h: (1280, 1328, 1440, 1688)
v: (1024, 1025, 1028, 1066)
size: 33.8 cm x 27.0 cm
border: 0.0 cm x 0.0 cm
Horizontal frequency range = 30..81 kHz
Vertical frequency range = 56..75 Hz
Maximum pixel clock = 140 MHz
Monitor Name: SyncMaster
Serial Number: HMDX914251

Vendor: ___
Product ID: 65535
Serial #: -1
Produced in week/year: 255/2245
EDID version: 255.255
Type: Digital
Size: 255 cm x 255 cm
Gamma=3.550
White (X,Y)=(0.999,0.999)
Supported Future Video Modes:
2288x1287@123Hz (id=65535)
2288x1287@123Hz (id=65535)
2288x1287@123Hz (id=65535)
2288x1287@123Hz (id=65535)
2288x1287@123Hz (id=65535)
2288x1287@123Hz (id=65535)
2288x1287@123Hz (id=65535)
2288x1287@123Hz (id=65535)
Supported VESA Video Modes:
720x400@70
720x400@88
640x480@60
640x480x67
640x480x72
640x480x75
800x600@56
800x600@60
800x600@72
800x600@75
832x624@75
1024x768@87 interlaced
1024x768@60
1024x768@70
1024x768@75
1280x1024@75
1152x870@75
Additional Video Mode:
clock=655.350000 MHz
h: (4095, 5118, 6141, 8190)
v: (4095, 4158, 4221, 8190)
size: 409.5 cm x 409.5 cm
border: 25.5 cm x 25.5 cm
Additional Video Mode:
clock=655.350000 MHz
h: (4095, 5118, 6141, 8190)
v: (4095, 4158, 4221, 8190)
size: 409.5 cm x 409.5 cm
border: 25.5 cm x 25.5 cm
Additional Video Mode:
clock=655.350000 MHz
h: (4095, 5118, 6141, 8190)
v: (4095, 4158, 4221, 8190)
size: 409.5 cm x 409.5 cm
border: 25.5 cm x 25.5 cm
Additional Video Mode:
clock=655.350000 MHz
h: (4095, 5118, 6141, 8190)
v: (4095, 4158, 4221, 8190)
size: 409.5 cm x 409.5 cm
border: 25.5 cm x 25.5 cm

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