Datasheet

FDS 6531/6532 005 Data Sheet 71M6531D/F-71M6532D/F
Rev 2 3
2 Functional Description ..................................................................................................................... 54
2.1 Theory of Operation ................................................................................................................... 54
2.2 System Timing Summary ........................................................................................................... 55
2.3 Battery Modes ............................................................................................................................ 56
2.3.1 BROWNOUT Mode ....................................................................................................... 57
2.3.2 LCD Mode ...................................................................................................................... 58
2.3.3 SLEEP Mode ................................................................................................................. 58
2.4 Fault and Reset Behavior .......................................................................................................... 60
2.4.1 Reset Mode .................................................................................................................... 60
2.4.2 Power Fault Circuit ........................................................................................................ 60
2.5 Wake-Up Behavior ..................................................................................................................... 61
2.5.1 Wake on PB ................................................................................................................... 61
2.5.2 Wake on Timer............................................................................................................... 61
2.6 Data Flow ................................................................................................................................... 61
2.7 CE/MPU Communication ........................................................................................................... 62
3 Application Information .................................................................................................................... 63
3.1 Connection of Sensors ............................................................................................................... 63
3.2 Connecting 5-V Devices ............................................................................................................ 63
3.3 Temperature Measurement ....................................................................................................... 64
3.4 Temperature Compensation ...................................................................................................... 64
3.4.1 Temperature Coefficients: ............................................................................................. 64
3.4.2 Temperature Compensation for VREF .......................................................................... 65
3.4.3 System Temperature Compensation ............................................................................. 65
3.4.4 Temperature Compensation for the RTC ...................................................................... 65
3.5 Connecting LCDs ....................................................................................................................... 66
3.6 Connecting I
2
C EEPROMs ........................................................................................................ 66
3.7 Connecting Three-Wire EEPROMs ........................................................................................... 67
3.8 UART0 (TX/RX) ......................................................................................................................... 67
3.9 Optical Interface (UART1).......................................................................................................... 67
3.10 Connecting the V1 Pin ............................................................................................................... 68
3.11 Connecting the Reset Pin .......................................................................................................... 69
3.12 Connecting the Emulator Port Pins ............................................................................................ 69
3.13 Connecting a Battery ................................................................................................................. 69
3.14 Flash Programming .................................................................................................................... 70
3.15 MPU Firmware ........................................................................................................................... 70
3.16 Crystal Oscillator ........................................................................................................................ 70
3.17 Meter Calibration ........................................................................................................................ 71
4 Firmware Interface ............................................................................................................................ 72
4.1 I/O RAM and SFR Map – Functional Order ............................................................................... 72
4.2 I/O RAM Description – Alphabetical Order ................................................................................ 77
4.3 CE Interface Description ............................................................................................................ 88
4.3.1 CE Program ................................................................................................................... 88
4.3.2 CE Data Format ............................................................................................................. 88
4.3.3 Constants ....................................................................................................................... 88
4.3.4 Environment ................................................................................................................... 88
4.3.5 CE Calculations ............................................................................................................. 89
4.3.6 CE Status and Control ................................................................................................... 89
4.3.7 CE Transfer Variables ................................................................................................... 92
4.3.8 Pulse Generation ........................................................................................................... 93
4.3.9 CE Calibration Parameters ............................................................................................ 94