This example will show you how to use hw_timer by led or logic analyzer:
- Using hw_timer to generate waveforms of different frequencies
- Observe the waveform with led or logic analyzer.

How to use example

Hardware Required

Connect GPIO12 with led1
Connect GPIO15 with led2

Configure the project

make menuconfig

Set serial port under Serial Flasher Options.

Build and Flash

Build the project and flash it to the board, then run monitor tool to view serial output:

make -j4 flash monitor

(To exit the serial monitor, type Ctrl-].)

Example Output

LOG:

I (228) hw_timer_example: Config gpio
I (220) gpio: GPIO[12]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0
I (224) gpio: GPIO[15]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0
I (248) hw_timer_example: Initialize hw_timer for callback1
I (258) hw_timer_example: Set hw_timer timing time 100us with reload
I (1268) hw_timer_example: Deinitialize hw_timer for callback1
I (1261) hw_timer_example: Initialize hw_timer for callback2
I (1264) hw_timer_example: Set hw_timer timing time 1ms with reload
I (2278) hw_timer_example: Set hw_timer timing time 10ms with reload
I (4278) hw_timer_example: Set hw_timer timing time 100ms with reload
I (7278) hw_timer_example: Cancel timing
I (7270) hw_timer_example: Initialize hw_timer for callback3
I (7272) hw_timer_example: Set hw_timer timing time 1ms with one-shot

WAVE FORM: