Datasheet

71M6521DE/DH/FE Data Sheet
Rev 3 Page: 3 of 107
Hardware Watchdog Timer ............................................................................................ 46
Program Security ........................................................................................................... 46
Test Ports ...................................................................................................................... 47
FUNCTIONAL DESCRIPTION ................................................................................................................... 48
Theory of Operation ..................................................................................................................... 48
System Timing Summary ............................................................................................................. 49
Battery Modes .............................................................................................................................. 50
MISSION ...................................................................................................................................... 51
BROWNOUT Mode ....................................................................................................... 51
LCD Mode ..................................................................................................................... 52
SLEEP Mode ................................................................................................................. 52
Fault and Reset Behavior ............................................................................................................ 57
Wake Up Behavior ....................................................................................................................... 57
Wake on PB................................................................................................................... 58
Wake on Timer .............................................................................................................. 58
Data Flow ..................................................................................................................................... 59
CE/MPU Communication ............................................................................................................. 59
APPLICATION INFORMATION ................................................................................................................. 60
Connection of Sensors (CT, Resistive Shunt) .............................................................................. 60
Distinction between 71M6521DE/71M6521FE and 71M6521DH Parts ....................................... 60
Temperature Measurement ......................................................................................................... 61
Temperature Compensation ........................................................................................................ 61
Temperature Compensation and Mains Frequency Stabilization for the RTC ............................. 64
Connecting 5 V Devices ............................................................................................................... 65
Connecting LCDs ......................................................................................................................... 66
Connecting I
2
C EEPROMs .......................................................................................................... 68
Connecting Three-Wire EEPROMs ............................................................................................. 69
UART0 (TX/RX) ........................................................................................................................... 69
Optical Interface ........................................................................................................................... 70
Connecting V1 and Reset Pins .................................................................................................... 70
Connecting the Emulator Port Pins .............................................................................................. 71
Crystal Oscillator .......................................................................................................................... 72
Flash Programming ..................................................................................................................... 72
MPU Firmware Library ................................................................................................................. 72
Meter Calibration ......................................................................................................................... 72
FIRMWARE INTERFACE .......................................................................................................................... 73
I/O RAM MAP – In Numerical Order ............................................................................................ 73
SFR MAP (SFRs Specific to the Teridian 80515) – In Numerical Order ...................................... 74
I/O RAM DESCRIPTION – Alphabetical Order ............................................................................ 75
CE Interface Description .............................................................................................................. 82
CE Program ................................................................................................................... 82