reef-pi :: An opensource reef tank controller based on Raspberry Pi.
- Thread starter Ranjib
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Des Westcott
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Just trying to think ahead a bit......
I see that the PH monitor build uses the same SDA / SCL pins (GPIO 2&3) as the PCA9685 uses. Can a single Pi3 run PWM lighting, a dosing pump and PH probe all on tise two pins? Is this what the I2C makes possible?
Des
I see that the PH monitor build uses the same SDA / SCL pins (GPIO 2&3) as the PCA9685 uses. Can a single Pi3 run PWM lighting, a dosing pump and PH probe all on tise two pins? Is this what the I2C makes possible?
Des
pickupman66
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Here is a bit more of the foods for today.
Hmm... Maybe I need to adjust my pwm frequency to get the jebao pumps to fire.
Hmm... Maybe I need to adjust my pwm frequency to get the jebao pumps to fire.
b4tn
Valuable Member
Here is a bit more of the foods for today.
Hmm... Maybe I need to adjust my pwm frequency to get the jebao pumps to fire.
Thanks a fatty! Are you smoking your food this year? This is the first year that I’m not doing the turkey in my ugly drum smoker. I normally do a turkey and a couple faties.
ScottBrew
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Here is a bit more of the foods for today.
Hmm... Maybe I need to adjust my pwm frequency to get the jebao pumps to fire.
Nice looking feast! What time we eatin'??? Are you trying to run the Jebao straight from the pi? I think you need a brushless DC controller.
OP
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WhoaHere is a bit more of the foods for today.
Hmm... Maybe I need to adjust my pwm frequency to get the jebao pumps to fire.
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Our dinner prep is on the way as well, keeping junior busy with pepper crushing work
Cranberry sauce is done , madam does all the side dishes, while i focus on the bird and beer. It’s no coding day
Cranberry sauce is done , madam does all the side dishes, while i focus on the bird and beer. It’s no coding day
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Yes. Like one wire , i2c is a bus, and many devices can connect to it. Just like public transport, it has its own challenges that we should be aware of. One bad actor, pwm speed etc are something to watch out for.
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We are going with Himalayan pink salt and saffron this year. Lots of thyme , rosemary and basil soaked stuffing (carrot, cerely , onion and bread crumbs )
As Ranjib said. You can use I2C over a few meters of wire, with special consideration (don’t use fast mode, increase pull-up resistors, etc).
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I think the board we are using, like pca9685, carrier board for ezo circuit all have pull up resistor. In fact I worry sooner or later we'll hit a state where we have to recommend folks to take out some of these pull up resistors. But thats a good problem to have
crusso1993
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@Ranjib - a hearty thank you on this day to give thanks! I realize it's a labor of love but to openly and freely share your knowledge, skills and, most importantly, time is a real gift for those of us who are lucky to determine which end of a soldering iron to hold!
And a big thanks to the rest of you Rough Reefers who share your experiences about reef-pi and everything else through R2R.
A Happy Thanksgiving to all!
Here is a bit more of the foods for today.
Hmm... Maybe I need to adjust my pwm frequency to get the jebao pumps to fire.
WOW[emoji779]️Man that looks intense! How long did the bacon macrame take [emoji23]. So here’s an idea to make yours even better! What would happen if I brined the bird before all that? It makes the meat so juicy tender. I mean it. I have always been the one to turn turkey down, just cuz it’s too way too dry the conventional zway. The makes the meat suck up the moisture and a little salt for flavor because of all the salt. I’m goin to try that!
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I dont know yet, it really depends upon the setup (wire length, types of devices, i2c mode, pull up resistors etc). I have not hit the limit, at most I have connected three. But we are likely to use more (since MCP23017 , the io expander support in 3.0 , is also i2c based)
ScottBrew
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Has pigpio been discussed for expansion?
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Nope. pigpio is software only right? Is there anything specific in pigpio that you think will be useful?
My current thought are around using MCP23017 to add another 16 I/O that can be used across outlets and inlets
The usual gating factor in I2C is bus capacitance - each device and wire adds some amount, up until you don’t get proper level transitions anymore. There are redrivers available, commonly used for the display information link in HDMI. I put one on the Pico design, which should overcome longer wire lengths.
Beyond that I recommend CAN or RS485 and a normal UART. The Pis UART is a bit gimpy depending on what hardware block is in use sadly.
Beyond that I recommend CAN or RS485 and a normal UART. The Pis UART is a bit gimpy depending on what hardware block is in use sadly.
LionHeart2017
Active Member
Got my self a dedicated Amazon fire 7 tablet today, so I can be posh and mount a tablet near my tank for control of reef-pi, well that is when I get all my bits, trouble I have here in UK is power relay, figuring out the nicest but safest way to do it.
Got in running in full screen as well[emoji2]
Got in running in full screen as well[emoji2]
OP
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Very coolGot my self a dedicated Amazon fire 7 tablet today, so I can be posh and mount a tablet near my tank for control of reef-pi, well that is when I get all my bits, trouble I have here in UK is power relay, figuring out the nicest but safest way to do it.
Got in running in full screen as well[emoji2]
