SAM7L128_14 Datasheet, PDF (460/549 Pages) ATMEL Corporation – AT91SAM ARM-based Flash MCU

33.5.4 Conversion Results
When a conversion is completed, the resulting 10-bit digital value is stored in the Channel Data Register
(ADC_CDR) of the current channel and in the ADC Last Converted Data Register (ADC_LCDR).
The channel EOC bit in the Status Register (ADC_SR) is set and the DRDY is set. In the case of a connected PDC
channel, DRDY rising triggers a data transfer request. In any case, either EOC and DRDY can trigger an interrupt.
Reading one of the ADC_CDR registers clears the corresponding EOC bit. Reading ADC_LCDR clears the DRDY
bit and the EOC bit corresponding to the last converted channel.
Figure 33-2. EOCx and DRDY Flag Behavior
Write the ADC_CR
with START = 1
Read the ADC_CDRx
Write the ADC_CR
with START = 1
Read the ADC_LCDR
CHx
(ADC_CHSR)
EOCx
(ADC_SR)
DRDY
(ADC_SR)
Conversion Time
Conversion Time
If the ADC_CDR is not read before further incoming data is converted, the corresponding Overrun Error (OVRE)
flag is set in the Status Register (ADC_SR).
In the same way, new data converted when DRDY is high sets the bit GOVRE (General Overrun Error) in
ADC_SR.
The OVRE and GOVRE flags are automatically cleared when ADC_SR is read.
SAM7L128/64 [DATASHEET]
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