Source code

# Okapi_Library

[![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.3766504.svg)](https://doi.org/10.5281/zenodo.3766504)

An Arduino-compatible library for utilizing the basic and logging features of the [Okapi](https://github.com/NorthernWidget-Skunkworks/Project-Okapi) data logger.

Data-logger management. Basic operations, power management, on-board sensing, and links to external devices. Manages logging, power, telemetry, and on-board sensing for the Okapi data logger. Supports solar charging, Particle Boron telemetry, external interrupt counting, RTC-driven sleep/wake cycles, and SD-card data logging.

Since 2026-09-23 Okapi is built on [NW_Logger](https://github.com/NorthernWidget/NW_Logger), the logger core it shares with Margay. That gives it Margay's card layout (`/<SN>/log00001.csv` and `sta00001.csv`, `HWTest.txt`; the old `NW/<SN>/Logs/LogN.txt` is gone), the status file with `watch(sensor)`, `note(word)` and the Note column, its serial number from Page 0 when the board is provisioned (NW-Provision) and from the last 8 bytes of EEPROM otherwise, and the camelCase names (`run`, `logStr`, `addDataPoint`, `initLogFile`, `resetWDT`, `powerAuto`, `powerAux`, `i2cState`, `getVoltage`, `setVoltage`, `readStr`). The PascalCase names still compile as deprecated forwarders for one release. `begin()` still returns whether the self-tests passed.

**Installation:** included in [NorthernWidget-libraries](https://github.com/NorthernWidget/NorthernWidget-libraries).

```cpp
#include <Okapi.h>

Okapi logger;

String update() {
  // Return a comma-separated string of external sensor readings.
  // Example: return myExternalSensor.getString();
  return "";
}

void setup() {
  Serial.begin(38400);
  if (!logger.begin("ExternalData,")) {
    Serial.println("begin() reported an error; check LED color for details.");
  }
}

void loop() {
  logger.run(update, 60);
}

See examples/ for this demo.

Full API reference: https://docs.northernwidget.com/Okapi_Library/ ```

Updated on 2026-09-23 at 22:44:32 +0000