Ras Pi Zero capability

[BiotechBen]

So would a Ras pi zero w be able to handle this kind of thing:

8 moisture sensors

8 temp sensors

16 LED indicators

 

And a program that was basically like:

If moisture= <20%  or >65%, then LED1=ON

If temp= <70°F or >85°F then LED2=ON

 

And before you ask, no this is not drugs, it's tomatoes, peppers, and peas

[badlou101]

if you can figure out how to connect that many sensors then it should work well 

[steelo]

On 2/13/2022 at 9:20 PM, BiotechBen said:

So would a Ras pi zero w be able to handle this kind of thing:

8 moisture sensors

8 temp sensors

16 LED indicators

 

And a program that was basically like:

If moisture= <20%  or >65%, then LED1=ON

If temp= <70°F or >85°F then LED2=ON

 

And before you ask, no this is not drugs, it's tomatoes, peppers, and peas

I'm not certain it has enough gpio pins, but yes, it can control sensors and leds without breaking a sweat.

[BiotechBen]

6 hours ago, steelo said:

I'm not certain it has enough gpio pins, but yes, it can control sensors and leds without breaking a sweat.

I'm thinking since I already have a thermometer there, I would just make it with 8LEDs to indicate that there is a deviance from accepted values

 

Or would it be easier for it to push me like an email or something that a sensor detected an out of range value

[steelo]

16 hours ago, BiotechBen said:

I'm thinking since I already have a thermometer there, I would just make it with 8LEDs to indicate that there is a deviance from accepted values

 

Or would it be easier for it to push me like an email or something that a sensor detected an out of range value

One thing that I forgot to mention is you will probably want to use a relay board to power the 8 leds if they are all on at once. The rpi's power supply is not very good to power more than a couple of leds simultaneously safely...they are cheap on ebay and it's not overly difficult, just adds a step to the build. A while back, I created a python reminder app that sent me a text message to remind me of appointments, etc. It used a free third party service (twilio) to send the sms. I think I still have the code, if you want to tailor it to your needs. I'm still a novice with python, so I'm sure you can improve it.

[BiotechBen]

3 hours ago, steelo said:

One thing that I forgot to mention is you will probably want to use a relay board to power the 8 leds if they are all on at once. The rpi's power supply is not very good to power more than a couple of leds simultaneously safely...they are cheap on ebay and it's not overly difficult, just adds a step to the build. A while back, I created a python reminder app that sent me a text message to remind me of appointments, etc. It used a free third party service (twilio) to send the sms. I think I still have the code, if you want to tailor it to your needs. I'm still a novice with python, so I'm sure you can improve it.

Ideally they wouldn't be all on at the same time, I would hope that I could moderate the temp fairly well and remember to water routinely. 

[mariushm]

On 2/14/2022 at 4:20 AM, BiotechBen said:

So would a Ras pi zero w be able to handle this kind of thing:

8 moisture sensors

8 temp sensors

16 LED indicators

 

And a program that was basically like:

If moisture= <20%  or >65%, then LED1=ON

If temp= <70°F or >85°F then LED2=ON

 

And before you ask, no this is not drugs, it's tomatoes, peppers, and peas

 

It depends on how the temperature and moisture sensors are interfacing with your raspberry pi zero.

Some are I2C , some are SPI, some are OneWire protocol ... if it's i2c, each device must have a unique address and some devices only allow to pick a unique address out of a pool of addresses (for example maximum 4 configurable I2c addresses so you could only have 4 sensors on a i2c bus, unless you use a i2c multiplexer).

 

You can use either led drivers or shift registers to drive that many leds and reduce the number of IO pins you need. Shift registers can be "bit-banged" so you don't waste your i2c/spi buses and just send bits across two wires.

 

An arduino or a PIC would be simpler to use and programmers are super cheap (arduino programmers are a few dollars, pic programmers are less than 15-20$)

 

[steelo]

1 hour ago, BiotechBen said:

Ideally they wouldn't be all on at the same time, I would hope that I could moderate the temp fairly well and remember to water routinely. 

I would lean towards a SMS/email solution or even creating a rpi server that you can log onto to get the information you need. LED's would work great, but would require additional equipment (relays) to work.

[mariushm]

No, relays are not needed ... depends on what leds we're talking about ... if it's puny indicator leds (like on computer case, power on and hdd activity leds) no need for relays... if you mean to actually light up the plants then yes, you would need relays.