daplink_flash: Add sensor logging example with statistics.

Author: nedseb

lib/daplink_flash/examples/sensor_log.py

@@ -0,0 +1,103 @@
+"""Log sensor data to flash and compute statistics.
+
+Writes 200 rows of simulated sensor data (temperature, humidity, pressure)
+to a CSV file on flash, then reads it back and computes min/max/average
+for each column.
+"""
+
+from machine import I2C
+from time import sleep_ms
+from daplink_flash import DaplinkFlash
+
+# --- Configuration ---
+NUM_ROWS = 200
+FILENAME = "SENSORS"
+EXT = "CSV"
+
+# --- Init ---
+i2c = I2C(1)
+flash = DaplinkFlash(i2c)
+print("DAPLink Flash WHO_AM_I: 0x{:02X}".format(flash.device_id()))
+
+# --- Generate and write data ---
+print("Writing {} rows to {}.{} ...".format(NUM_ROWS, FILENAME, EXT))
+flash.set_filename(FILENAME, EXT)
+flash.clear_flash()
+sleep_ms(500)
+
+flash.write_line("row;temperature;humidity;pressure")
+
+# Simple pseudo-random generator (linear congruential)
+seed = 12345
+for row in range(NUM_ROWS):
+    seed = (seed * 1103515245 + 12345) & 0x7FFFFFFF
+    temp = 20.0 + (seed % 1000) / 100.0
+    seed = (seed * 1103515245 + 12345) & 0x7FFFFFFF
+    hum = 30.0 + (seed % 4000) / 100.0
+    seed = (seed * 1103515245 + 12345) & 0x7FFFFFFF
+    pres = 990.0 + (seed % 5000) / 100.0
+
+    line = "{};{:.1f};{:.1f};{:.1f}".format(row, temp, hum, pres)
+    flash.write(line + "\n")
+
+print("Write complete.")
+sleep_ms(100)
+
+# --- Read back and compute statistics ---
+print("Reading back...")
+content = flash.read()
+lines = content.decode().split("\n")
+
+# Skip header and empty lines
+data_lines = [l for l in lines[1:] if l]
+print("Read {} data rows.".format(len(data_lines)))
+
+temp_sum = 0.0
+hum_sum = 0.0
+pres_sum = 0.0
+temp_min = 999.0
+temp_max = -999.0
+hum_min = 999.0
+hum_max = -999.0
+pres_min = 9999.0
+pres_max = -9999.0
+count = 0
+
+for line in data_lines:
+    parts = line.split(";")
+    if len(parts) != 4:
+        continue
+    t = float(parts[1])
+    h = float(parts[2])
+    p = float(parts[3])
+
+    temp_sum += t
+    hum_sum += h
+    pres_sum += p
+
+    if t < temp_min:
+        temp_min = t
+    if t > temp_max:
+        temp_max = t
+    if h < hum_min:
+        hum_min = h
+    if h > hum_max:
+        hum_max = h
+    if p < pres_min:
+        pres_min = p
+    if p > pres_max:
+        pres_max = p
+
+    count += 1
+
+print()
+print("=== Statistics ({} rows) ===".format(count))
+print("              Min      Avg      Max")
+print("Temp (C):  {:7.1f}  {:7.1f}  {:7.1f}".format(
+    temp_min, temp_sum / count, temp_max))
+print("Hum (%):   {:7.1f}  {:7.1f}  {:7.1f}".format(
+    hum_min, hum_sum / count, hum_max))
+print("Pres (hPa):{:7.1f}  {:7.1f}  {:7.1f}".format(
+    pres_min, pres_sum / count, pres_max))
+print()
+print("File size: {} bytes".format(len(content)))