I'd like to blink one LED using a timer interrupt. I tried using several timer interrupt libraries, such as mstimer2, but I get compilation errors.
Maybe this is because the nano33ble board uses nrf52840 unlike the usual Arduino.
Then, is there a timer library for the nano33ble board?
I'd appreciate it if you could let me know.
Thank you in advance. 
I'd like to blink one LED using a timer interrupt.
I cannot help with your query, but are you sure that you need to use a timer interrupt ? What sort of blinking period and accuracy do you need and what else is the sketch doing ?
Maybe this is because the nano33ble board uses nrf52840 unlike the usual Arduino.
Not maybe, it is the reason.
Hello. Thank you for your answer.
There are two main functions that I want to use. (Use an IMU sensor and three LED)
-
LED1 or LED2 operates the Blink according to IMU sensor values.
(The left and right LED operate like a direction light depending on the slope value of the IMU.)
-
LED3 continues to Blink regardless of previous function This function can be turned on/off through the app.
(App control via BLE communication)
I was thinking of using timer interrupt in function number 2, but can it be simply implemented as a millis() function?
can it be simply implemented as a millis() function?
Yes
See Using millis() for timing. A beginners guide, Several things at the same time and the BlinkWithoutDelay example in the IDE