25-04-2017, 23:25
(25-04-2017, 22:55)clubjoker Wrote: Another minor issue I've noticed is that the first pressure measurement from the RX+ (from the onboard BMP280) after switch on, is a glitch: 747mBar. The is updated to a more believable reading (e.g. 1010mBar) after a minute or so, I imagine on the second reading. Don't know why this is happening. I'm concerned that when I put the system into service, recording weather history, this glitch will pollute the data. Anyone else seen this? If the hardware is being slow to respond, is there a software workaround to wait a bit longer before taking the first reading, or simply reject 747mBar, or something more elegant?
I never seen it happened, and it just should not happen. By those signs, I'm afraid that something may be wrong. Try to remember if you ever had the Meduino powered by the USB, leaving the board without the external power supply. By the signs, it probable that the 74AHC244 chip was become damaged. Really hope I'm wrong. The first thing you should try to achieve is making that the 3.3V regulator don't warm.
Also try to run the I2C_Scanner and the FlashMemory_test utilities. The I2C_Scanner should consistently be able to detect all your I2C devices (RTC, Pressure Sensor and SHT31) at all speeds.