===== 08 G08 GP1 08 READBACK | BIOS 19951204 System ROM Version 3.0 11/18/96 A
BadVaddr as the group starts: 00000480
GP1(08h)=v for v 00-FF: GPUSTAT bits 13-22 read at once, shifted down 13, in hex.
psx-spx: bit14=v.7 bit16=v.6 bits17-18=v.0-1 bit19=v.2 bit20=v.3 bit21=v.4 bit22=v.5.
00: 001 011 021 031 041 051 061 071 080 090 0a0 0b0 0c0 0d0 0e0 0f1
10: 101 111 121 131 141 151 161 170 180 191 1a1 1b1 1c1 1d1 1e1 1f1
20: 200 211 221 231 241 251 261 271 281 291 2a1 2b1 2c1 2d1 2e1 2f1
30: 301 311 321 331 341 351 361 371 381 391 3a1 3b1 3c1 3d1 3e1 3f1
40: 009 019 029 039 049 059 069 079 089 099 0a9 0b9 0c9 0d9 0e9 0f9
50: 109 119 129 139 149 159 169 179 189 199 1a9 1b9 1c9 1d9 1e9 1f9
60: 209 219 229 239 249 259 269 279 289 299 2a9 2b9 2c9 2d9 2e9 2f9
70: 309 319 329 339 349 359 369 379 389 399 3a9 3b9 3c9 3d9 3e9 3f9
80: 003 013 023 033 043 053 063 072 082 092 0a2 0b2 0c2 0d2 0e2 0f2
90: 103 113 123 133 143 153 163 173 182 193 1a3 1b3 1c3 1d3 1e3 1f2
a0: 202 213 223 233 243 253 263 273 283 293 2a3 2b3 2c3 2d3 2e3 2f3
b0: 303 313 323 333 343 353 363 373 383 393 3a3 3b3 3c3 3d3 3e3 3f3
c0: 00b 01b 02b 03b 04b 05b 06b 07b 08b 09b 0ab 0bb 0cb 0db 0eb 0fb
d0: 10b 11b 12b 13b 14b 15b 16b 17b 18b 19b 1ab 1bb 1cb 1db 1eb 1fb
e0: 20b 21b 22b 23b 24b 25b 26b 27b 28b 29b 2ab 2bb 2cb 2db 2eb 2fb
f0: 30b 31b 32b 33b 34b 35b 36b 37b 38b 39b 3ab 3bb 3cb 3db 3eb 3fb
Values whose bits 14 and 16-22 differ from psx-spx: 0
GP1(08h)=27: at once 564e200f, 2000 cycles on 564e200f
GP1(08h)=FFFFFF: 567f600f
GP1(48h)=27, the mirror: 5602200f
GP1(88h)=03, the mirror: 5602200f
GP1(05h)=Y100 X64 changes GPUSTAT bits 00000000
GP1(06h)=100-200 changes GPUSTAT bits 00000000
GP1(07h)=50-60 changes GPUSTAT bits 00000000
GP1(03h)=1: 5682200f
GP1(03h)=0: 5602200f
GP1(03h)=FFFFFE: 5602200f
GP1(00h): at once 14802000, after an IRQ0 14802000 (psx-spx 14802000)
Done.