I made a board to use as an altimeter on road trips. It has a SparkFun Serial LED display, a Freescale MPL3115A2 on a SparkFun breakout board, and a Picaxe 14M2, all connected via I2C.
On initial power up at 3.3V from a regulated power supply. it drew 10 MA and all voltages were as expected.
The first test program displayed a word counter successfully. Only the display was activated.
On the next step I changed the test program as shown to display the integer part of the altitude.
Then the current draw went up to 30 MA, and tests showed both SCL and SDA clamped at 0.7 V. This is due to the sensor board. All I did was to load the program.
I have not been able to change this. Do I have a dud sensor, or some design problem? I am reluctant to order a replacement without explanation.
On initial power up at 3.3V from a regulated power supply. it drew 10 MA and all voltages were as expected.
The first test program displayed a word counter successfully. Only the display was activated.
On the next step I changed the test program as shown to display the integer part of the altitude.
Then the current draw went up to 30 MA, and tests showed both SCL and SDA clamped at 0.7 V. This is due to the sensor board. All I did was to load the program.
I have not been able to change this. Do I have a dud sensor, or some design problem? I am reluctant to order a replacement without explanation.
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