Light Metering - Canon EOS 55 Service Manual

Part 2: Technical Information
2. 7 Light Metering
1.
When SWI is turned on the MPU starts the exposure metering sequence.
2.
Toe MPU sets the metering areas through
DO
~
D2
and the sensor output is applied
to the A/D convector through the AEAD line.
3. Toe MPU reads the compensation data from the EEPROM applies
it
to the data an
determines the exposure value.
4. Toe MPU checks the camera mode setting and determines the aperture and/or shut-
ter speeds and communicates this data to the LCD-DR
5. Toe LCD-DR displays the data on the LCD.
(RREQ)
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LCD Dr
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Fig. 2-28 Light Metering
2-36