SAM7S256_14 Datasheet, PDF (599/775 Pages) ATMEL Corporation – ARM-based Flash MCU

40.4 SAM7S512 Errata - Revision A Parts
Refer to Section 40.1 “Marking” on page 595.
Note: AT91SAM7S512 Revision A chip ID is: 0x270B 0A40.
40.4.1 Analog-to-Digital Converter (ADC)
40.4.1.1 ADC: DRDY Bit Cleared
The DRDY Flag should be clear only after a read of ADC_LCDR (Last Converted Data Register). A read of any
ADC_CDRx register (Channel Data Register) automatically clears the DRDY flag.
Problem Fix/Workaround:
None
40.4.1.2 ADC: DRDY not Cleared on Disable
When reading LCDR at the same instant as an end of conversion, with DRDY already active, DRDY is kept active
regardless of the enable status of the current channel. This sets DRDY, whereas new data is not stored.
Problem Fix/Workaround
None
40.4.1.3 ADC: DRDY Possibly Skipped due to CDR Read
Reading CDR for channel “y” at the same instant as an end of conversion on channel “x” with EOC[x] already
active, leads to skipping to set the DRDY flag if channel “x” is enabled.
Problem Fix/Workaround
Use of DRDY functionality with access to CDR registers should be avoided.
40.4.1.4 ADC: Possible Skip on DRDY when Disabling a Channel
DRDY does not rise when disabling channel “y” at the same time as an end of “x” channel conversion, although
data is stored into CDRx and LCDR.
Problem Fix/Workaround
None.
40.4.1.5 ADC: GOVRE Bit is not Updated
Read of the Status Register at the same instant as an end of conversion leads to skipping the update of the
GOVRE (general overrun) flag. GOVRE is neither reset nor set.
For example, if reading the status while an end of conversion is occurring and:
1. GOVRE is active but DRDY is inactive, does not correspond to a new general overrun condition but the
GOVRE flag is not reset.
2. GOVRE is inactive but DRDY is active, does correspond to a new general overrun condition but the
GOVRE flag is not set.
Problem Fix/Workaround
None
40.4.1.6 ADC: GOVRE Bit is not Set when Reading CDR
When reading CDRy (Channel Data Register y) at the same instant as an end of conversion on channel “x” with the
following conditions:
• EOC[x] already active,
• DRDY already active,
SAM7S Series [DATASHEET]
6175M–ATARM–26-Oct-12
599