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91b2e171 1##
50bd5d25 2## This file is part of the libsigrokdecode project.
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3##
4## Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
5##
6## This program is free software; you can redistribute it and/or modify
7## it under the terms of the GNU General Public License as published by
8## the Free Software Foundation; either version 3 of the License, or
9## (at your option) any later version.
10##
11## This program is distributed in the hope that it will be useful,
12## but WITHOUT ANY WARRANTY; without even the implied warranty of
13## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14## GNU General Public License for more details.
15##
16## You should have received a copy of the GNU General Public License
17## along with this program; if not, see <http://www.gnu.org/licenses/>.
18##
19
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20# TODO:
21# - EDID < 1.3
1063646c 22# - add short annotations
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23# - Signal level standard field in basic display parameters block
24# - Additional color point descriptors
25# - Additional standard timing descriptors
26# - Extensions
27
28import sigrokdecode as srd
29import os
30
31EDID_HEADER = [0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00]
32OFF_VENDOR = 8
33OFF_VERSION = 18
34OFF_BASIC = 20
35OFF_CHROM = 25
36OFF_EST_TIMING = 35
37OFF_STD_TIMING = 38
38OFF_DET_TIMING = 54
39OFF_NUM_EXT = 126
40OFF_CHECKSUM = 127
41
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42# Pre-EDID established timing modes
43est_modes = [
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44 '720x400@70Hz',
45 '720x400@88Hz',
46 '640x480@60Hz',
47 '640x480@67Hz',
48 '640x480@72Hz',
49 '640x480@75Hz',
50 '800x600@56Hz',
51 '800x600@60Hz',
52 '800x600@72Hz',
53 '800x600@75Hz',
54 '832x624@75Hz',
55 '1024x768@87Hz(i)',
56 '1024x768@60Hz',
57 '1024x768@70Hz',
58 '1024x768@75Hz',
59 '1280x1024@75Hz',
60 '1152x870@75Hz',
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61]
62
63# X:Y display aspect ratios, as used in standard timing modes
64xy_ratio = [
65 (16, 10),
66 (4, 3),
67 (5, 4),
e4f82268 68 (16, 9),
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69]
70
5cdc02d4 71# Annotation classes
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72ANN_FIELDS = 0
73ANN_SECTIONS = 1
74
75class Decoder(srd.Decoder):
12851357 76 api_version = 2
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77 id = 'edid'
78 name = 'EDID'
b7a7e6f5 79 longname = 'Extended Display Identification Data'
a465436e 80 desc = 'Data structure describing display device capabilities.'
91b2e171 81 license = 'gplv3+'
9e1437a0 82 inputs = ['i2c']
91b2e171 83 outputs = ['edid']
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84 annotations = (
85 ('fields', 'EDID structure fields'),
86 ('sections', 'EDID structure sections'),
87 )
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88
89 def __init__(self, **kwargs):
90 self.state = None
91 # Received data items, used as an index into samplenum/data
92 self.cnt = 0
93 # Start/end sample numbers per data item
94 self.sn = []
95 # Received data
96 self.cache = []
97
8915b346 98 def start(self):
be465111 99 self.out_ann = self.register(srd.OUTPUT_ANN)
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100
101 def decode(self, ss, es, data):
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102 cmd, data = data
103
104 # We only care about actual data bytes that are read (for now).
105 if cmd != 'DATA READ':
106 return
107
91b2e171 108 self.cnt += 1
e4f82268 109 self.sn.append([ss, es])
91b2e171 110 self.cache.append(data)
2a706c20 111 # debug
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112
113 if self.state is None:
114 # Wait for the EDID header
115 if self.cnt >= OFF_VENDOR:
116 if self.cache[-8:] == EDID_HEADER:
117 # Throw away any garbage before the header
118 self.sn = self.sn[-8:]
119 self.cache = self.cache[-8:]
2a706c20 120 self.cnt = 8
91b2e171 121 self.state = 'edid'
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122 self.put(self.sn[0][0], es, self.out_ann,
123 [ANN_SECTIONS, ['Header']])
124 self.put(self.sn[0][0], es, self.out_ann,
125 [ANN_FIELDS, ['Header pattern']])
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126 elif self.state == 'edid':
127 if self.cnt == OFF_VERSION:
128 self.decode_vid(-10)
129 self.decode_pid(-8)
130 self.decode_serial(-6)
131 self.decode_mfrdate(-2)
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132 self.put(self.sn[OFF_VENDOR][0], es, self.out_ann,
133 [ANN_SECTIONS, ['Vendor/product']])
91b2e171 134 elif self.cnt == OFF_BASIC:
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135 self.put(self.sn[OFF_VERSION][0], es, self.out_ann,
136 [ANN_SECTIONS, ['EDID Version']])
137 self.put(self.sn[OFF_VERSION][0], self.sn[OFF_VERSION][1],
138 self.out_ann, [ANN_FIELDS,
139 ["Version %d" % self.cache[-2]]])
140 self.put(self.sn[OFF_VERSION+1][0], self.sn[OFF_VERSION+1][1],
141 self.out_ann, [ANN_FIELDS,
142 [ "Revision %d" % self.cache[-1]]])
91b2e171 143 elif self.cnt == OFF_CHROM:
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144 self.put(self.sn[OFF_BASIC][0], es, self.out_ann,
145 [ANN_SECTIONS, ['Basic display']])
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146 self.decode_basicdisplay(-5)
147 elif self.cnt == OFF_EST_TIMING:
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148 self.put(self.sn[OFF_CHROM][0], es, self.out_ann,
149 [ANN_SECTIONS, ['Color characteristics']])
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150 self.decode_chromaticity(-10)
151 elif self.cnt == OFF_STD_TIMING:
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152 self.put(self.sn[OFF_EST_TIMING][0], es, self.out_ann,
153 [ANN_SECTIONS, ['Established timings']])
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154 self.decode_est_timing(-3)
155 elif self.cnt == OFF_DET_TIMING:
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156 self.put(self.sn[OFF_STD_TIMING][0], es, self.out_ann,
157 [ANN_SECTIONS, ['Standard timings']])
158 self.decode_std_timing(self.cnt - 16)
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159 elif self.cnt == OFF_NUM_EXT:
160 self.decode_descriptors(-72)
161 elif self.cnt == OFF_CHECKSUM:
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162 self.put(ss, es, self.out_ann,
163 [0, ['Extensions present: %d' % self.cache[self.cnt-1]]])
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164 elif self.cnt == OFF_CHECKSUM+1:
165 checksum = 0
166 for i in range(128):
167 checksum += self.cache[i]
168 if checksum % 256 == 0:
09059016 169 csstr = 'OK'
91b2e171 170 else:
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171 csstr = 'WRONG!'
172 self.put(ss, es, self.out_ann, [0, ['Checksum: %d (%s)' % (
173 self.cache[self.cnt-1], csstr)]])
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174 self.state = 'extensions'
175 elif self.state == 'extensions':
176 pass
177
178 def ann_field(self, start, end, annotation):
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179 self.put(self.sn[start][0], self.sn[end][1],
180 self.out_ann, [ANN_FIELDS, [annotation]])
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181
182 def lookup_pnpid(self, pnpid):
1063646c 183 pnpid_file = os.path.join(os.path.dirname(__file__), 'pnpids.txt')
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184 if os.path.exists(pnpid_file):
185 for line in open(pnpid_file).readlines():
186 if line.find(pnpid + ';') == 0:
187 return line[4:].strip()
188 return ''
189
190 def decode_vid(self, offset):
191 pnpid = chr(64 + ((self.cache[offset] & 0x7c) >> 2))
192 pnpid += chr(64 + (((self.cache[offset] & 0x03) << 3)
193 | ((self.cache[offset+1] & 0xe0) >> 5)))
194 pnpid += chr(64 + (self.cache[offset+1] & 0x1f))
195 vendor = self.lookup_pnpid(pnpid)
196 if vendor:
09059016 197 pnpid += ' (%s)' % vendor
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198 self.ann_field(offset, offset+1, pnpid)
199
200 def decode_pid(self, offset):
09059016 201 pidstr = 'Product 0x%.2x%.2x' % (self.cache[offset+1], self.cache[offset])
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202 self.ann_field(offset, offset+1, pidstr)
203
204 def decode_serial(self, offset):
205 serialnum = (self.cache[offset+3] << 24) \
206 + (self.cache[offset+2] << 16) \
207 + (self.cache[offset+1] << 8) \
208 + self.cache[offset]
209 serialstr = ''
210 is_alnum = True
211 for i in range(4):
212 if not chr(self.cache[offset+3-i]).isalnum():
213 is_alnum = False
214 break
215 serialstr += chr(self.cache[offset+3-i])
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216 serial = serialstr if is_alnum else str(serialnum)
217 self.ann_field(offset, offset+3, 'Serial ' + serial)
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218
219 def decode_mfrdate(self, offset):
220 datestr = ''
221 if self.cache[offset]:
09059016 222 datestr += 'week %d, ' % self.cache[offset]
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223 datestr += str(1990 + self.cache[offset+1])
224 if datestr:
09059016 225 self.ann_field(offset, offset+1, 'Manufactured ' + datestr)
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226
227 def decode_basicdisplay(self, offset):
228 # Video input definition
229 vid = self.cache[offset]
230 if vid & 0x80:
231 # Digital
09059016 232 self.ann_field(offset, offset, 'Video input: VESA DFP 1.')
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233 else:
234 # Analog
235 sls = (vid & 60) >> 5
09059016 236 self.ann_field(offset, offset, 'Signal level standard: %.2x' % sls)
91b2e171 237 if vid & 0x10:
09059016 238 self.ann_field(offset, offset, 'Blank-to-black setup expected')
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239 syncs = ''
240 if vid & 0x08:
241 syncs += 'separate syncs, '
242 if vid & 0x04:
243 syncs += 'composite syncs, '
244 if vid & 0x02:
245 syncs += 'sync on green, '
246 if vid & 0x01:
247 syncs += 'Vsync serration required, '
248 if syncs:
09059016 249 self.ann_field(offset, offset, 'Supported syncs: %s' % syncs[:-2])
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250 # Max horizontal/vertical image size
251 if self.cache[offset+1] != 0 and self.cache[offset+2] != 0:
252 # Projectors have this set to 0
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253 sizestr = '%dx%dcm' % (self.cache[offset+1], self.cache[offset+2])
254 self.ann_field(offset+1, offset+2, 'Physical size: ' + sizestr)
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255 # Display transfer characteristic (gamma)
256 if self.cache[offset+3] != 0xff:
257 gamma = (self.cache[offset+3] + 100) / 100
09059016 258 self.ann_field(offset+3, offset+3, 'Gamma: %1.2f' % gamma)
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259 # Feature support
260 fs = self.cache[offset+4]
261 dpms = ''
262 if fs & 0x80:
263 dpms += 'standby, '
264 if fs & 0x40:
265 dpms += 'suspend, '
266 if fs & 0x20:
267 dpms += 'active off, '
268 if dpms:
09059016 269 self.ann_field(offset+4, offset+4, 'DPMS support: %s' % dpms[:-2])
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270 dt = (fs & 0x18) >> 3
271 dtstr = ''
272 if dt == 0:
273 dtstr = 'Monochrome'
274 elif dt == 1:
275 dtstr = 'RGB color'
276 elif dt == 2:
e4f82268 277 dtstr = 'non-RGB multicolor'
91b2e171 278 if dtstr:
09059016 279 self.ann_field(offset+4, offset+4, 'Display type: %s' % dtstr)
91b2e171 280 if fs & 0x04:
09059016 281 self.ann_field(offset+4, offset+4, 'Color space: standard sRGB')
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282 # Save this for when we decode the first detailed timing descriptor
283 self.have_preferred_timing = (fs & 0x02) == 0x02
284 if fs & 0x01:
285 gft = ''
286 else:
287 gft = 'not '
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288 self.ann_field(offset+4, offset+4,
289 'Generalized timing formula: %ssupported' % gft)
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290
291 def convert_color(self, value):
292 # Convert from 10-bit packet format to float
293 outval = 0.0
294 for i in range(10):
295 if value & 0x01:
296 outval += 2 ** -(10-i)
297 value >>= 1
298 return outval
299
300 def decode_chromaticity(self, offset):
301 redx = (self.cache[offset+2] << 2) + ((self.cache[offset] & 0xc0) >> 6)
302 redy = (self.cache[offset+3] << 2) + ((self.cache[offset] & 0x30) >> 4)
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303 self.ann_field(offset, offset+9, 'Chromacity red: X %1.3f, Y %1.3f' % (
304 self.convert_color(redx), self.convert_color(redy)))
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305
306 greenx = (self.cache[offset+4] << 2) + ((self.cache[offset] & 0x0c) >> 6)
307 greeny = (self.cache[offset+5] << 2) + ((self.cache[offset] & 0x03) >> 4)
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308 self.ann_field(offset, offset+9, 'Chromacity green: X %1.3f, Y %1.3f' % (
309 self.convert_color(greenx), self.convert_color(greeny)))
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310
311 bluex = (self.cache[offset+6] << 2) + ((self.cache[offset+1] & 0xc0) >> 6)
312 bluey = (self.cache[offset+7] << 2) + ((self.cache[offset+1] & 0x30) >> 4)
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313 self.ann_field(offset, offset+9, 'Chromacity blue: X %1.3f, Y %1.3f' % (
314 self.convert_color(bluex), self.convert_color(bluey)))
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315
316 whitex = (self.cache[offset+8] << 2) + ((self.cache[offset+1] & 0x0c) >> 6)
317 whitey = (self.cache[offset+9] << 2) + ((self.cache[offset+1] & 0x03) >> 4)
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318 self.ann_field(offset, offset+9, 'Chromacity white: X %1.3f, Y %1.3f' % (
319 self.convert_color(whitex), self.convert_color(whitey)))
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320
321 def decode_est_timing(self, offset):
322 # Pre-EDID modes
323 bitmap = (self.cache[offset] << 9) \
324 + (self.cache[offset+1] << 1) \
325 + ((self.cache[offset+2] & 0x80) >> 7)
326 modestr = ''
327 for i in range(17):
328 if bitmap & (1 << (16-i)):
329 modestr += est_modes[i] + ', '
330 if modestr:
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331 self.ann_field(offset, offset+2,
332 'Supported establised modes: %s' % modestr[:-2])
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333
334 def decode_std_timing(self, offset):
335 modestr = ''
336 for i in range(0, 16, 2):
337 if self.cache[offset+i] == 0x01 and self.cache[offset+i+1] == 0x01:
338 # Unused field
339 continue
340 x = (self.cache[offset+i] + 31) * 8
341 ratio = (self.cache[offset+i+1] & 0xc0) >> 6
342 ratio_x, ratio_y = xy_ratio[ratio]
343 y = x / ratio_x * ratio_y
344 refresh = (self.cache[offset+i+1] & 0x3f) + 60
09059016 345 modestr += '%dx%d@%dHz, ' % (x, y, refresh)
91b2e171 346 if modestr:
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347 self.ann_field(offset, offset + 15,
348 'Supported standard modes: %s' % modestr[:-2])
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349
350 def decode_detailed_timing(self, offset):
351 if offset == -72 and self.have_preferred_timing:
352 # Only on first detailed timing descriptor
353 section = 'Preferred'
354 else:
355 section = 'Detailed'
356 section += ' timing descriptor'
2ef80066 357 self.put(self.sn[offset][0], self.sn[offset+17][1],
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358 self.out_ann, [ANN_SECTIONS, [section]])
359
360 pixclock = float((self.cache[offset+1] << 8) + self.cache[offset]) / 100
09059016 361 self.ann_field(offset, offset+1, 'Pixel clock: %.2f MHz' % pixclock)
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362
363 horiz_active = ((self.cache[offset+4] & 0xf0) << 4) + self.cache[offset+2]
09059016 364 self.ann_field(offset+2, offset+4, 'Horizontal active: %d' % horiz_active)
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365
366 horiz_blank = ((self.cache[offset+4] & 0x0f) << 8) + self.cache[offset+3]
2ef80066 367 self.ann_field(offset+2, offset+4, 'Horizontal blanking: %d' % horiz_blank)
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368
369 vert_active = ((self.cache[offset+7] & 0xf0) << 4) + self.cache[offset+5]
09059016 370 self.ann_field(offset+5, offset+7, 'Vertical active: %d' % vert_active)
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371
372 vert_blank = ((self.cache[offset+7] & 0x0f) << 8) + self.cache[offset+6]
2ef80066 373 self.ann_field(offset+5, offset+7, 'Vertical blanking: %d' % vert_blank)
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374
375 horiz_sync_off = ((self.cache[offset+11] & 0xc0) << 2) + self.cache[offset+8]
09059016 376 self.ann_field(offset+8, offset+11, 'Horizontal sync offset: %d' % horiz_sync_off)
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377
378 horiz_sync_pw = ((self.cache[offset+11] & 0x30) << 4) + self.cache[offset+9]
2ef80066 379 self.ann_field(offset+8, offset+11, 'Horizontal sync pulse width: %d' % horiz_sync_pw)
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380
381 vert_sync_off = ((self.cache[offset+11] & 0x0c) << 2) \
382 + ((self.cache[offset+10] & 0xf0) >> 4)
2ef80066 383 self.ann_field(offset+8, offset+11, 'Vertical sync offset: %d' % vert_sync_off)
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384
385 vert_sync_pw = ((self.cache[offset+11] & 0x03) << 4) \
386 + (self.cache[offset+10] & 0x0f)
2ef80066 387 self.ann_field(offset+8, offset+11, 'Vertical sync pulse width: %d' % vert_sync_pw)
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388
389 horiz_size = ((self.cache[offset+14] & 0xf0) << 4) + self.cache[offset+12]
390 vert_size = ((self.cache[offset+14] & 0x0f) << 8) + self.cache[offset+13]
09059016 391 self.ann_field(offset+12, offset+14, 'Physical size: %dx%dmm' % (horiz_size, vert_size))
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392
393 horiz_border = self.cache[offset+15]
2ef80066 394 self.ann_field(offset+15, offset+15, 'Horizontal border: %d pixels' % horiz_border)
91b2e171 395 vert_border = self.cache[offset+16]
2ef80066 396 self.ann_field(offset+16, offset+16, 'Vertical border: %d lines' % vert_border)
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397
398 features = 'Flags: '
399 if self.cache[offset+17] & 0x80:
400 features += 'interlaced, '
401 stereo = (self.cache[offset+17] & 0x60) >> 5
402 if stereo:
403 if self.cache[offset+17] & 0x01:
404 features += '2-way interleaved stereo ('
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405 features += ['right image on even lines',
406 'left image on even lines',
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407 'side-by-side'][stereo-1]
408 features += '), '
409 else:
410 features += 'field sequential stereo ('
411 features += ['right image on sync=1', 'left image on sync=1',
412 '4-way interleaved'][stereo-1]
413 features += '), '
414 sync = (self.cache[offset+17] & 0x18) >> 3
415 sync2 = (self.cache[offset+17] & 0x06) >> 1
416 posneg = ['negative', 'positive']
417 features += 'sync type '
418 if sync == 0x00:
419 features += 'analog composite (serrate on RGB)'
420 elif sync == 0x01:
421 features += 'bipolar analog composite (serrate on RGB)'
422 elif sync == 0x02:
423 features += 'digital composite (serrate on composite polarity ' \
09059016 424 + (posneg[sync2 & 0x01]) + ')'
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425 elif sync == 0x03:
426 features += 'digital separate ('
2a706c20 427 features += 'Vsync polarity ' + (posneg[(sync2 & 0x02) >> 1])
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428 features += ', Hsync polarity ' + (posneg[sync2 & 0x01])
429 features += ')'
430 features += ', '
431 self.ann_field(offset+17, offset+17, features[:-2])
432
433 def decode_descriptor(self, offset):
434 tag = self.cache[offset+3]
435 if tag == 0xff:
436 # Monitor serial number
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437 self.put(self.sn[offset][0], self.sn[offset+17][1], self.out_ann,
438 [ANN_SECTIONS, ['Serial number']])
91b2e171 439 text = bytes(self.cache[offset+5:][:13]).decode(encoding='cp437', errors='replace')
2ef80066 440 self.ann_field(offset, offset+17, text.strip())
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441 elif tag == 0xfe:
442 # Text
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443 self.put(self.sn[offset][0], self.sn[offset+17][1], self.out_ann,
444 [ANN_SECTIONS, ['Text']])
91b2e171 445 text = bytes(self.cache[offset+5:][:13]).decode(encoding='cp437', errors='replace')
2ef80066 446 self.ann_field(offset, offset+17, text.strip())
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447 elif tag == 0xfc:
448 # Monitor name
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449 self.put(self.sn[offset][0], self.sn[offset+17][1], self.out_ann,
450 [ANN_SECTIONS, ['Monitor name']])
91b2e171 451 text = bytes(self.cache[offset+5:][:13]).decode(encoding='cp437', errors='replace')
2ef80066 452 self.ann_field(offset, offset+17, text.strip())
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453 elif tag == 0xfd:
454 # Monitor range limits
455 self.put(self.sn[offset][0], self.sn[offset+17][1], self.out_ann,
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456 [ANN_SECTIONS, ['Monitor range limits']])
457 self.ann_field(offset+5, offset+5, 'Minimum vertical rate: %dHz' %
91b2e171 458 self.cache[offset+5])
09059016 459 self.ann_field(offset+6, offset+6, 'Maximum vertical rate: %dHz' %
91b2e171 460 self.cache[offset+6])
09059016 461 self.ann_field(offset+7, offset+7, 'Minimum horizontal rate: %dkHz' %
91b2e171 462 self.cache[offset+7])
09059016 463 self.ann_field(offset+8, offset+8, 'Maximum horizontal rate: %dkHz' %
91b2e171 464 self.cache[offset+8])
09059016 465 self.ann_field(offset+9, offset+9, 'Maximum pixel clock: %dMHz' %
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466 (self.cache[offset+9] * 10))
467 if self.cache[offset+10] == 0x02:
468 # Secondary GTF curve supported
09059016 469 self.ann_field(offset+10, offset+17, 'Secondary timing formula supported')
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470 elif tag == 0xfb:
471 # Additional color point data
472 self.put(self.sn[offset][0], self.sn[offset+17][1], self.out_ann,
09059016 473 [ANN_SECTIONS, ['Additional color point data']])
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474 elif tag == 0xfa:
475 # Additional standard timing definitions
476 self.put(self.sn[offset][0], self.sn[offset+17][1], self.out_ann,
09059016 477 [ANN_SECTIONS, ['Additional standard timing definitions']])
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478 else:
479 self.put(self.sn[offset][0], self.sn[offset+17][1], self.out_ann,
09059016 480 [ANN_SECTIONS, ['Unknown descriptor']])
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481
482 def decode_descriptors(self, offset):
483 # 4 consecutive 18-byte descriptor blocks
484 for i in range(offset, 0, 18):
485 if self.cache[i] != 0 and self.cache[i+1] != 0:
486 self.decode_detailed_timing(i)
487 else:
1063646c 488 if self.cache[i+2] == 0 or self.cache[i+4] == 0:
91b2e171 489 self.decode_descriptor(i)