rootScript
Active member
I2C Port Expander - carrier Shield - Teensy 3.1 Project guidance
Hello,
I am building an aquarium controller/monitor using a Teensy 3.1. I wanted to ask for some general advice before I get my fingers burnt.
I am going to use quite a lot of sensors to monitor my marine saltwater tank; here is the list so far:
TMP102 (i2c ambient room temperature - 1.4 to 3.6VDC) x1
DS18B2 (1-Wire Digital Thermometer - 3.0-5.5V input voltage) x2
eC circuit (i2c salinity meter - 2.7 to 5.5V) x1
pH circuit (i2c PH meter - 2.7 to 5.5V) x1
TSL2561 (i2c Light Sensor - 3-5VDC - I2C 7-bit address 0x29) x1
TCS34725 (i2c Colour Sensor - 2.7-3.6V - I2C 7-bit addresses 0x39, 0x29, 0x49, selectable with jumpers) x1
So you can see already I have quite a few I2C devices to attach, so I wanted to build an expander shield to stack on top of the Teensy to allow me to connect maybe 5-8 I2C sensors in total.
I don't know if it complicates things, but aswell as monitoring using I2C, I will be controlling two 24V pumps, and two 52W LED arrays, using PWM, and maybe eight Solid State Relays for 240VAC.
There seems to be quite a few I2C port expanders ICs out there, and I was hoping that you guys with experience would help me choose a shortlist of chips to experiment with.
When choosing a component like this, what criteria do you use to compare ICs?
For me, all I would like is something that is code friendly to a newcomer, and something that is small enough to fit on top of a Teensy. I will need to add small easy to plug connectors for each device on to the shield (maybe small JST?).
I would be really grateful if you guys could advise me which port expanders to use, I don't have the experience in this field, and would really welcome some advice so that i can experiment & learn.
Carlos
Hello,
I am building an aquarium controller/monitor using a Teensy 3.1. I wanted to ask for some general advice before I get my fingers burnt.
I am going to use quite a lot of sensors to monitor my marine saltwater tank; here is the list so far:
TMP102 (i2c ambient room temperature - 1.4 to 3.6VDC) x1
DS18B2 (1-Wire Digital Thermometer - 3.0-5.5V input voltage) x2
eC circuit (i2c salinity meter - 2.7 to 5.5V) x1
pH circuit (i2c PH meter - 2.7 to 5.5V) x1
TSL2561 (i2c Light Sensor - 3-5VDC - I2C 7-bit address 0x29) x1
TCS34725 (i2c Colour Sensor - 2.7-3.6V - I2C 7-bit addresses 0x39, 0x29, 0x49, selectable with jumpers) x1
So you can see already I have quite a few I2C devices to attach, so I wanted to build an expander shield to stack on top of the Teensy to allow me to connect maybe 5-8 I2C sensors in total.
I don't know if it complicates things, but aswell as monitoring using I2C, I will be controlling two 24V pumps, and two 52W LED arrays, using PWM, and maybe eight Solid State Relays for 240VAC.
There seems to be quite a few I2C port expanders ICs out there, and I was hoping that you guys with experience would help me choose a shortlist of chips to experiment with.
When choosing a component like this, what criteria do you use to compare ICs?
For me, all I would like is something that is code friendly to a newcomer, and something that is small enough to fit on top of a Teensy. I will need to add small easy to plug connectors for each device on to the shield (maybe small JST?).
I would be really grateful if you guys could advise me which port expanders to use, I don't have the experience in this field, and would really welcome some advice so that i can experiment & learn.
Carlos
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