Datasheet ADAS1000, ADAS1000-1, ADAS1000-2 (Analog Devices) - 82

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ADAS1000/ ADAS1000-1/ ADAS1000-2 Data Sheet SOFTWARE FLOWCHART
Figure 84 shows a suggested sequence of steps to be taken to interface to multiple ADAS1000/ADAS1000-1/ADAS1000-2 devices.
POWER UP ADAS1000 DEVICES WAIT FOR POR ROUTINE TO COMPLETE, 1.5ms INITIALIZE SLAVE DEVICES INITIALIZE MASTER DEVICE ENABLING CONVERSION ISSUE READ FRAME COMMAND (WRITE TO 0x40) NO DRDY LOW? YES ISSUE SCLK CYCLES (SDI = 0) TO CLOCK FRAME DATA OUT AT PROGRAMMED DATA RATE IS CRC NO DISCARD CORRECT? FRAME DATA YES NO ACTIVITY ON SDI? YES ADAS1000 STOPS CONVERTING, SDI WORD USED TO RECONFIGURE DEVICE RETURN NO TO ECG CAPTURE? YES ISSUE READ FRAME COMMAND (WRITE TO 0x40) NO POWER-DOWN? YES ECG CAPTURE COMPLETE POWER-DOWN ADAS1000 ECGCTL = 0x0
8 -03
ADAS1000 GOES INTO
0
POWER-DOWN MODE
66 09 Figure 84. Suggested Software Flowchart for Interfacing to Multiple ADAS1000/ADAS1000-1/ADAS1000-2 Devices Rev. C | Page 82 of 85 Document Outline Features Applications General Description Revision History Functional Block Diagram Specifications Noise Performance Timing Characteristics Standard Serial Interface Secondary Serial Interface (Master Interface for Customer-Based Digital Pace Algorithm) ADAS1000/ADAS1000-1 Only Absolute Maximum Ratings Thermal Resistance ESD Caution Pin Configurations and Function Descriptions Typical Performance Characteristics Applications Information Overview ECG Inputs—Electrodes/Leads ECG Channel Electrode/Lead Formation and Input Stage Configuration Analog Lead Mode and Calculation Digital Lead Mode and Calculation Electrode Mode: Single-Ended Input Electrode Configuration Electrode Mode: Common Electrode A and Electrode B Configurations Defibrillator Protection ESIS Filtering ECG Path Input Multiplexing Common-Mode Selection and Averaging Wilson Central Terminal (WCT) Right Leg Drive/Reference Drive Calibration DAC Gain Calibration Lead-Off Detection DC Lead-Off Detection DC Lead-Off and High Gains DC Lead-Off Debounce Timer AC Lead-Off Detection ACLO and Common-Mode Configuration ADC Out of Range Shield Driver Respiration (ADAS1000 Model Only) Internal Respiration Capacitors External Respiration Path External Respiration Capacitors Respiration Carrier Frequency Evaluating Respiration Performance Extend Switch On Respiration Paths Pacing Artifact Detection Function (ADAS1000 Only) Choice of Leads Detection Algorithm Overview Pace Edge Threshold Pace Level Threshold Pace Amplitude Threshold Pace Validation Filters Pace Width Filter Biventricular Pacers Pace Detection Measurements Evaluating Pace Detection Performance Pace Width Pace Latency Pace Detection via Secondary Serial Interface (ADAS1000 and ADAS1000-1 Only) Filtering Voltage Reference Gang Mode Operation Master/Slave Synchronizing Devices Calibration Common Mode Right Leg Drive Sequencing Devices into Gang Mode Number of Devices in Gang Mode Interfacing in Gang Mode Serial Interfaces Standard Serial Interface Write Mode Write/Read Data Format Data Frames/Packets Read Mode Serial Clock Rate Data Rate and Skip Mode Data Ready (DRDYB) Detecting Missed Conversion Data SPI Interface Resync CRC Word Clocks Secondary Serial Interface RESETB PDB Function SPI Output Frame Structure (ECG and Status Data) SPI Register Definitions and Memory Map Control Registers Details Examples of Interfacing to the ADAS1000 Example 1: Initialize the ADAS1000 for ECG Capture and Start Streaming Data Example 2: Enable Respiration and Stream Conversion Data Example 3: DC Lead-Off and Stream Conversion Data Example 4: Configure 150 Hz Test Tone Sine Wave on Each ECG Channel and Stream Conversion Data Example 5: Enable Pace Detection and Stream Conversion Data Example 6: Writing to Master and Slave Devices and Streaming Conversion Data Slave Configuration Master Configuration Software Flowchart Power Supply, Grounding, and Decoupling Strategy AVDD ADCVDD and DVDD Supplies Unused Pins/Paths Layout Recommendations Outline Dimensions Ordering Guide