reef-pi :: An opensource reef tank controller based on Raspberry Pi.

theatrus

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Spent some time poking at the PWM support, and can confirm the math... doesn't work at arbitrary frequencies (the frequency is written out as the period value multiplied out, and not the inverse as it should be). This also maps to the duty cycle being very wrong at frequencies not == 100.
 

b4tn

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Spent some time poking at the PWM support, and can confirm the math... doesn't work at arbitrary frequencies (the frequency is written out as the period value multiplied out, and not the inverse as it should be). This also maps to the duty cycle being very wrong at frequencies not == 100.

Is this for the PCA9685 support or RPI built in PWM?
 

dmolavi

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Here is the sensor that I got. Kinda wondering if its waterproof...
1549419712638.jpeg
 

bishoptf

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I got my Drok sensors...with red, white and yellow wires. Is this correct:
Red - VCC
Yellow - data
White - ground

OR

Red - VCC
Yellow - ground
White - data

Not sure which ones you have but if they are the ones with the silicon jackets - https://www.amazon.com/T-PRO-DS18b2...id=1549419698&sr=8-1&keywords=DS18B20+silicon

According to the specs:
Product Parameter
- Power supply range: DC3.0V to 5.0
- Operating temperature range: -55°C to +125°C
- Accuracy: ±0.5°C (From -10°C to +85°C )
- Lead max to +85°C
- Data transmission mode: 9 - 12 adjustable resolution
- Output leads: Red (VDD+), Yellow(DATA) , White(GND)
- Stainless steel pipe: Diamter 6mm,Length 50mm
- Cable Material: silica gel
- Single Length of Cable : 1M/3.3 Ft

Although I have not used them I think @DirtDiggler2823 has used them, maybe he can chime in...
 

dmolavi

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Not sure which ones you have but if they are the ones with the silicon jackets - https://www.amazon.com/T-PRO-DS18b2...id=1549419698&sr=8-1&keywords=DS18B20+silicon

According to the specs:
Product Parameter
- Power supply range: DC3.0V to 5.0
- Operating temperature range: -55°C to +125°C
- Accuracy: ±0.5°C (From -10°C to +85°C )
- Lead max to +85°C
- Data transmission mode: 9 - 12 adjustable resolution
- Output leads: Red (VDD+), Yellow(DATA) , White(GND)
- Stainless steel pipe: Diamter 6mm,Length 50mm
- Cable Material: silica gel
- Single Length of Cable : 1M/3.3 Ft

Although I have not used them I think @DirtDiggler2823 has used them, maybe he can chime in...

Mine looks exactly like the one there....
 

theatrus

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I think @Bigtrout was having issues with the pca9685 not being able to use anything less than 1500 frequency.

Both are likely broken in different ways. There is a larger change coming to the PCA9685 driver which may fix the other half of the issues.
 

Bigtrout

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I got my Drok sensors...with red, white and yellow wires. Is this correct:
Red - VCC
Yellow - data
White - ground

OR

Red - VCC
Yellow - ground
White - data
Red=VCC
White=GND
Yellow=data
Do u like the quality? Compared to some others they are alot better IMHO.
 

Bigtrout

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Spent some time poking at the PWM support, and can confirm the math... doesn't work at arbitrary frequencies (the frequency is written out as the period value multiplied out, and not the inverse as it should be). This also maps to the duty cycle being very wrong at frequencies not == 100.
This corresponds with my meter getting strange duty cycle readings. The frequency readings were confirmed with 2 seperate meters, but my second meter doesnt read duty cycle so didnt report that without confirmation.
 

crusso1993

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thanks just trying get it back moved here a couple years ago lost all my sps coral in the move going soft coral this time, here are some pics of old tank

1.JPG


2.JPG


3.JPG

Beautiful!
 
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