Lizard Labs Peripheral Reflex System

1. Lizard LabsPeripheral Reflex System EFM32 Training Module

2. Peripheral Reflex System Z Z Z Z Brain Z Z Sensor nerve Motor nerve Spine

3. Peripheral Reflex System Z Z Z Z ARMCortex-M3 processor Z Z Peripheralreflex system Timer ADC

4. Reflexes versus Interrupts ARMCortex-M3 processor CPU IRQ Energy Efficient Peripherals Timer ADC

5. Reflexes versus Interrupts ARMCortex-M3 processor UNKNOWNDELAY CPU IRQ Energy Efficient Peripherals Timer ADC

6. Reflexes versus Interrupts ARMCortex-M3 processor HIGHCURRENT CONSUMPTION UNKNOWNDELAY CPU IRQ Energy Efficient Peripherals Timer ADC

7. Reflexes versus Interrupts Z Z Z ARMCortex-M3 processor Energy Efficient Peripherals PRS Timer ADC

8. Peripheral Reflex System Z Z Z ARM Cortex-M3 processor PRS Producers PRS Consumers Timer GPIO ADC DAC PeripheralReflexSystem

9. Peripheral Reflex System Z Z Z ARM Cortex-M3 processor PRS Producers PRS Consumers Timer GPIO ADC DAC PeripheralReflexSystem

10. Example: ADC samples to RAM ADC ADC Peripheral Reflex System Timer Start conversion Overflow Analog input DMA Request Direct Memory Access RAM Sample done Sample Data Sample Data • SW Examples: • AN0021 Analog to Digital Converter • AN0013 Direct Memory Access

11. Example: Pulse width measurement Timer Reset & Start Analog input + Peripheral Reflex System ACMP Capture Overflow Reference - Reference Analog input Reflex signal TIMER Count value Capture Reset & Start Capture Reset & Start • SW Example: AN0025 Peripheral Reflex System

12. Peripherals With PRS Support • Reflex Producers • ACMP • ADC • DAC • GPIO • RTC • BURTC • TIMER • LETIMER • LESENSE • UART • USART • USB • VCMP • Reflex Consumers • ADC • DAC • TIMER • LESENSE • UART • USART • PCNT Reflex signals

13. PRS and Energy Modes CPU and Memory Clock Management Energy Management ARM Cortex-M3 processor High Freq Crystal Osc High Freq RC Osc Voltage Regulator Embedded Trace Macrocell Voltage Comparator ARM Cortex-M processor Memory Protection Unit MemoryProtection Unit Low Freq Crystal Osc Low Freq RC Osc Power-on Reset Brown-out Detector Flash Program Memory RAM Memory Debug Interface DMA Ultra Low Freq RC Osc Auxiliary RC Osc Auxiliary RC Osc Back-up Power Domain 32-bit bus Peripheral Reflex System Serial Interfaces I/O Ports Timers and Triggers Analog Modules Security Low Energy Sensor IF USART External Bus Interface Timer/Counter ADC DAC UART AES Accelerator TFT Driver Low Energy Timer Real Time Counter LCD Controller Operational Amplifier Low Energy UART I2C External Interrupt General Purpose I/O Pulse Counter Watchdog Timer Analog Comparator Pin Reset GPIO Wake-up USB Backup RTC Available down to: EM0 Run Mode EM1 Sleep EM2 Deep Sleep EM3 Stop Mode EM4 Shutoff Mode

14. PRS API in emlib • Use emlib API functions to configure PRS: • 1) Configure producer as normal • 2) Configure PRS channel • 3) Configure consumer

15. PRS on external pins • PRS channels 0-3 can be routed to external pins • Useful when debugging autonomous peripherals Timer ADC

16. Summary • PRS advantages • Energy Efficient • Autonomous • Fast • Predictable latency • Highly configurable

17. www.silabs.com