added RTC date/time stamp

Author: jedgarpark

Pulse_Oximeter_Logger/pulse_oximeter_logger.py

@@ -18,6 +18,7 @@
 import busio
 import digitalio
 import storage
+import adafruit_pcf8523
 import _bleio
 import adafruit_ble
 from adafruit_ble.advertising.standard import Advertisement
@@ -32,13 +33,32 @@
 vfs = storage.VfsFat(sd_card)
 storage.mount(vfs, "/sd_card")
 
+log_interval = 2  # you can adjust this to log at a different rate
+
+# RTC setup
+I2C = busio.I2C(board.SCL, board.SDA)
+rtc = adafruit_pcf8523.PCF8523(I2C)
+
+days = ("Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday")
+
+set_time = False
+if set_time:  # change to True if you want to write the time!
+    #             year, mon, date, hour, min, sec, wday, yday, isdst
+    t = time.struct_time((2020, 4, 21, 16, 36, 0, 2, -1, -1))
+    # you must set year, mon, date, hour, min, sec and weekday
+    # yearday  not supported, isdst can be set but we don't use it at this time
+    print("Setting time to:", t)  # uncomment for debugging
+    rtc.datetime = t
+    print()
+
 # PyLint can't find BLERadio for some reason so special case it here.
 ble = adafruit_ble.BLERadio()  # pylint: disable=no-member
 
 pulse_ox_connection = None
 initial_time = time.monotonic()
 
 while True:
+    t = rtc.datetime
     print("Scanning for Pulse Oximeter...")
     for adv in ble.start_scan(Advertisement, timeout=5):
         name = adv.complete_name
@@ -80,7 +100,10 @@
                     valid, spo2, pulse_rate, pleth, finger = values
                     if not valid:
                         continue
-
+                    if (
+                            pulse_rate == 255
+                    ):  # device sends 255 as pulse until it has a valid read
+                        continue
                     print(
                         "SpO2: {}%  | ".format(spo2),
                         "Pulse Rate: {} BPM  | ".format(pulse_rate),
@@ -96,13 +119,24 @@
                                 "Seconds since current data log started:",
                                 int(time_stamp),
                             )
+                            sdc.write(
+                                "{} {}/{}/{} {}:{}:{} ".format(
+                                    days[t.tm_wday],
+                                    t.tm_mday,
+                                    t.tm_mon,
+                                    t.tm_year,
+                                    t.tm_hour,
+                                    t.tm_min,
+                                    t.tm_sec,
+                                )
+                            )
                             sdc.write(
                                 "{}, {}, {}, {:.2f}\n".format(
                                     int(time_stamp), spo2, pulse_rate, pleth
                                 )
                             )
 
-                            time.sleep(2)
+                            time.sleep(log_interval)
                     except OSError:
                         pass
                     except RuntimeError: