Datasheet
Table Of Contents
- 1 Hardware Description
- 1.1 Hardware Overview
- 1.2 Analog Front End (AFE)
- 1.3 Digital Computation Engine (CE)
- 1.4 80515 MPU Core
- 1.4.1 Memory Organization and Addressing
- 1.4.2 Special Function Registers (SFRs)
- 1.4.3 Generic 80515 Special Function Registers
- 1.4.4 Special Function Registers (SFRs) Specific to the 71M6531D/F and 71M6532D/F
- 1.4.5 Instruction Set
- 1.4.6 UARTs
- 1.4.7 Timers and Counters
- 1.4.8 WD Timer (Software Watchdog Timer)
- 1.4.9 Interrupts
- 1.5 On-Chip Resources
- 1.5.1 Oscillator
- 1.5.2 Internal Clocks
- 1.5.3 Real-Time Clock (RTC)
- 1.5.4 Temperature Sensor
- 1.5.5 Physical Memory
- 1.5.6 Optical Interface
- 1.5.7 Digital I/O – 71M6531D/F
- 1.5.8 Digital I/O – 71M6532D/F
- 1.5.9 Digital IO – Common Characteristics for 71M6531D/F and 71M6532D/F
- 1.5.10 LCD Drivers – 71M6531D/F
- 1.5.11 LCD Drivers – 71M6532D/F
- 1.5.12 LCD Drivers – Common Characteristics for 71M6531D/F and 71M6532D/F
- 1.5.13 Battery Monitor
- 1.5.14 EEPROM Interface
- 1.5.15 SPI Slave Port
- 1.5.16 Hardware Watchdog Timer
- 1.5.17 Test Ports (TMUXOUT pin)
- 2 Functional Description
- 3 Application Information
- 3.1 Connection of Sensors
- 3.2 Connecting 5-V Devices
- 3.3 Temperature Measurement
- 3.4 Temperature Compensation
- 3.5 Connecting LCDs
- 3.6 Connecting I2C EEPROMs
- 3.7 Connecting Three-Wire EEPROMs
- 3.8 UART0 (TX/RX)
- 3.9 Optical Interface (UART1)
- 3.10 Connecting the V1 Pin
- 3.11 Connecting the Reset Pin
- 3.12 Connecting the Emulator Port Pins
- 3.13 Connecting a Battery
- 3.14 Flash Programming
- 3.15 MPU Firmware
- 3.16 Crystal Oscillator
- 3.17 Meter Calibration
- 4 Firmware Interface
- 4.1 I/O RAM and SFR Map – Functional Order
- 4.2 I/O RAM Description – Alphabetical Order
- 4.3 CE Interface Description
- 5 Electrical Specifications
- 5.1 Absolute Maximum Ratings
- 5.2 Recommended External Components
- 5.3 Recommended Operating Conditions
- 5.4 Performance Specifications
- 5.4.1 Input Logic Levels
- 5.4.2 Output Logic Levels
- 5.4.3 Power-Fault Comparator
- 5.4.4 Battery Monitor
- 5.4.5 Supply Current
- 5.4.6 V3P3D Switch
- 5.4.7 2.5 V Voltage Regulator
- 5.4.8 Low-Power Voltage Regulator
- 5.4.9 Crystal Oscillator
- 5.4.10 LCD DAC
- 5.4.11 LCD Drivers
- 5.4.12 Optical Interface
- 5.4.13 Temperature Sensor
- 5.4.14 VREF
- 5.4.15 ADC Converter, V3P3A Referenced
- 5.5 Timing Specifications
- 5.6 Typical Performance Data
- 5.7 71M6531D/F Package
- 5.8 71M6532D/F Package
- 5.9 Pin Descriptions
- 6 Ordering Information
- 7 Related Information
- 8 Contact Information
- Appendix A: Acronyms
- Appendix B: Revision History
FDS 6531/6532 005 Data Sheet 71M6531D/F-71M6532D/F
Rev 2 61
2.5 Wake-Up Behavior
As described above, the part will always wake up in MISSION mode when system power is restored.
Additionally, the part will wake up in BROWNOUT mode when PB rises (push button is pressed) or when
a timeout of the wake-up timer occurs.
2.5.1 Wake on PB
If the part is in SLEEP or LCD mode, it can be awakened by a rising edge on the PB pin. This pin is normally
pulled to GND and can be pulled high by a push button depression. Before the PB signal rises, the MPU
is in reset due to WAKE being low. When PB rises, WAKE rises and within three crystal cycles, the MPU
begins to execute. The MPU can determine whether the PB signal woke it up by checking the IE_PB flag.
Figure 25 shows the Wake Up timing.
For debouncing, the PB pin is monitored by a state machine operating from a 32 Hz clock. This circuit
will reject between 31 ms and 62 ms of noise. Detection hardware will ignore all transitions after the initial
rising edge. This will continue until the MPU clears the IE_PB bit.
Figure 25: Wake Up Timing
2.5.2 Wake on Timer
If the part is in SLEEP or LCD mode, it can be awakened by the wake-up timer. Until this timer times out,
the MPU is in reset due to WAKE being low. When the wake-up timer times out, the WAKE signal rises
and within three crystal cycles, the MPU begins to execute. The MPU can determine whether the timer
woke it by checking the AUTOWAKE interrupt flag (IE_WAKE).
The wake-up timer begins timing when the part enters LCD or SLEEP mode. Its duration is controlled by
WAKE_PRD[2:0] and WAKE_RES. WAKE_RES selects a timer LSB of either 1 minute (WAKE_RES = 1) or
2.5 seconds (WAKE_RES = 0). WAKE_PRD[2:0] selects a duration of from 1 to 7 LSBs.
The timer is armed by WAKE_ARM = 1. It must be armed at least three RTC cycles before SLEEP or
LCD_ONLY is initiated. Setting WAKE_ARM presets the timer with the values in WAKE_RES and WAKE_PRD
and readies the timer to start when the processor writes to SLEEP or LCD_ONLY. The timer is reset and
disarmed whenever the processor is awake. Thus, if it is desired to wake the MPU periodically (every 5
seconds, for example) the timer must be rearmed every time the MPU is awakened.
2.6 Data Flow
The data flow between the Compute Engine (CE) and the MPU is shown in Figure 26. In a typical ap-
plication, the 32-bit CE sequentially processes the samples from the voltage inputs on pins IA, VA, IB and
VB, performing calculations to measure active power (Wh), reactive power (VARh), A
2
h and V
2
h for four-
quadrant metering. These measurements are then accessed by the MPU, processed further and output
using the peripheral devices available to the MPU.