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@OneSadCookie
Created October 22, 2010 23:24
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EDID decoding on the Mac, to find out what resolutions and rates the Mac is seeing reported.
http://cgit.freedesktop.org/xorg/app/edid-decode/plain/edid-decode.c
compile with:
gcc edid-decode.c -o edid-decode
get EDID from IORegistryExplorer (mine, an old 24" Apple Cinema Display, is attached).
Convert to binary with this command:
ruby -e 'File.open("edid", "wb").write(File.read("edid.txt").split.map { |s| ("0x"+s).to_i(16) }.inject("", "<<"))'
Decode your EDID with this command:
./edid-decode edid
My output is attached.
00 ff ff ff ff ff ff 00 06 10 1c 92 de ce 00 02
15 11 01 03 80 31 1f 78 2e fd 45 a3 57 4a 9e 25
13 50 54 00 00 00 d1 00 01 01 01 01 01 01 01 01
01 01 01 01 01 01 28 3c 80 a0 70 b0 23 40 30 20
36 00 ef 36 11 00 00 1a 00 00 00 ff 00 32 41 37
32 31 33 4a 4e 58 4d 4e 0a 20 00 00 00 fc 00 43
69 6e 65 6d 61 20 48 44 0a 20 20 20 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 e4
40 01 02 00 00 00 00 7e 24 01 a5 00 ff ff 03 1a
1a a8 01 00 00 00 00 00 40 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 57
Extracted contents:
header: 00 ff ff ff ff ff ff 00
serial number: 06 10 1c 92 de ce 00 02 15 11
version: 01 03
basic params: 80 31 1f 78 2e
chroma info: fd 45 a3 57 4a 9e 25 13 50 54
established: 00 00 00
standard: d1 00 01 01 01 01 01 01 01 01 01 01 01 01 01 01
descriptor 1: 28 3c 80 a0 70 b0 23 40 30 20 36 00 ef 36 11 00 00 1a
descriptor 2: 00 00 00 ff 00 32 41 37 32 31 33 4a 4e 58 4d 4e 0a 20
descriptor 3: 00 00 00 fc 00 43 69 6e 65 6d 61 20 48 44 0a 20 20 20
descriptor 4: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
extensions: 01
checksum: e4
Manufacturer: APP Model 921c Serial Number 33607390
Made week 21 of 2007
EDID version: 1.3
Digital display
Maximum image size: 49 cm x 31 cm
Gamma: 2.20
DPMS levels: Off
Supported color formats: RGB 4:4:4, YCrCb 4:2:2
Default (sRGB) color space is primary color space
First detailed timing is preferred timing
Established timings supported:
Standard timings supported:
1920x1200@60Hz
Detailed mode: Clock 154.000 MHz, 495 mm x 310 mm
1920 1968 2000 2080 hborder 0
1200 1203 1209 1235 vborder 0
+hsync -vsync
Serial number: 2A7213JNXMN
Monitor name: Cinema HD
Manufacturer-specified data, tag 0
Has 1 extension blocks
Checksum: 0xe4
DI extension block
EDID block does NOT conform to EDID 1.3!
Digital display field contains garbage: 1
Missing monitor ranges
@efalk
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efalk commented Mar 12, 2020

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