Video screen
m 15-inch cathode-ray tube (CRT)
m 0.28 mm dot pitch
CD-ROM specifications
m Disc diameter 120 millimeters (4.7 inches)
and 80 mm
m Scanning velocity 1.2–1.4 meters per second
m Rotation speed (varies over radius):
Normal speed ~530 to 230 rpm
Double speed ~1060 to 460 rpm
Quadruple speed ~2120 to 920 rpm
m Average latency (varies over radius):
Normal speed ~55 to 130 milliseconds (ms)
Double speed ~27.5 to 65 ms
Quadruple speed ~13.75 to 32.5 ms
m Blocks per rotation ~8.4 to 19.5 variable
m Average access time (typical):
Normal speed 380 ms
Double speed 270 ms
Quadruple speed 200 ms
Data
m Data capacity 656 megabytes (MB), Mode 1
748 MB, Mode 2
m Number of blocks per disc 336,150
m Data per block 2048 bytes, Mode 1
2336 bytes, Mode 2
m Address description Minutes, seconds, blocks
Audio capacity
m Playing time 74 minutes, 42 seconds
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