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Read <strong>Data</strong> The following procedure is used to read the data stored in the EEPROM memory:<br />
114 <strong>AT89C51ID2</strong><br />
Check EEBUSY flag<br />
If the user application interrupts routines use XRAM memory space: Save and<br />
disable interrupts.<br />
Load DPTR with the address to read<br />
Set bit EEE of EECON register<br />
Execute a MOVX A, @DPTR<br />
Clear bit EEE of EECON register<br />
Restore interrupts.<br />
Figure 45. Recommended EEPROM <strong>Data</strong> Read Sequence<br />
EEPROM <strong>Data</strong> Read<br />
Sequence<br />
EEBusy<br />
Cleared?<br />
Save & Disable IT<br />
EA= 0<br />
EEPROM <strong>Data</strong> Mapping<br />
EECON = 02h (EEE=1)<br />
<strong>Data</strong> Read<br />
DPTR= Address<br />
ACC= <strong>Data</strong><br />
Exec: MOVX A, @DPTR<br />
Last Byte<br />
to Read?<br />
EEPROM <strong>Data</strong> Mapping<br />
EECON = 00h (EEE = 0<br />
Restore IT<br />
4289A–8051–09/03