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Post by Deleted on Jan 25, 2021 11:04:36 GMT
Might be a bit of long shot, but has anyone on here any knowledge of raspberry pi projects, looking at building something for the boat in terms of sensors and a bit stuck on how to add the sensors whilst using the pins for a GSM card..
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Post by Jim on Jan 25, 2021 11:17:18 GMT
Never quite got round to exploring raspberry Pi. There's certainly lots of tutorials etc on t'internet.
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Post by Telemachus on Jan 25, 2021 11:27:02 GMT
Might be a bit of long shot, but has anyone on here any knowledge of raspberry pi projects, looking at building something for the boat in terms of sensors and a bit stuck on how to add the sensors whilst using the pins for a GSM card.. Ive done a bit with Pis. But the first stage in any project is to decide on the core of it, and that decision is based on what it needs to do, obviously! Pis are good for certain stuff, very accessible and cheap. HOWEVER I am not convinced they are the best thing for control and monitoring purposes. The reason being they have a large and very complex (relatively) fast processor, and run under a linux-type operating system. In other words, there are huge overheads if what you want to do is relatively simple. Consequently you are never quite sure exactly what the processor is doing and the power consumption is high, which is an issue if you are not on shore power. They are way over -specced for many jobs. For more simple control and monitoring projects, I’d suggest looking at an Arduino. These are on a completely different level of complexity, you are much more in direct contact with the hardware and the power consumption is an order of magnitude less. i would only go for a Pi if you really need a sophisticated graphic display on a computer monitor/tv
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Post by JohnV on Jan 25, 2021 11:29:56 GMT
Never quite got round to exploring raspberry Pi. There's certainly lots of tutorials etc on t'internet. Like this one ?
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Post by Jim on Jan 25, 2021 11:33:26 GMT
Never quite got round to exploring raspberry Pi. There's certainly lots of tutorials etc on t'internet. Like this one ?
John Cleese went on to to many employment training videos.
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Post by Deleted on Jan 25, 2021 11:35:27 GMT
Might be a bit of long shot, but has anyone on here any knowledge of raspberry pi projects, looking at building something for the boat in terms of sensors and a bit stuck on how to add the sensors whilst using the pins for a GSM card.. Ive done a bit with Pis. But the first stage in any project is to decide on the core of it, and that decision is based on what it needs to do, obviously! Pis are good for certain stuff, very accessible and cheap. HOWEVER I am not convinced they are the best thing for control and monitoring purposes. The reason being they have a large and very complex (relatively) fast processor, and run under a linux-type operating system. In other words, there are huge overheads if what you want to do is relatively simple. Consequently you are never quite sure exactly what the processor is doing and the power consumption is high, which is an issue if you are not on shore power. They are way over -specced for many jobs. For more simple control and monitoring projects, I’d suggest looking at an Arduino. These are on a completely different level of complexity, you are much more in direct contact with the hardware and the power consumption is an order of magnitude less. i would only go for a Pi if you really need a sophisticated graphic display on a computer monitor/tv Was actually thinking of setting up and playing around at home on my pi 3, then transferring over to the raspberry pico
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Post by Deleted on Jan 25, 2021 11:40:23 GMT
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Post by Telemachus on Jan 25, 2021 11:52:37 GMT
Ive done a bit with Pis. But the first stage in any project is to decide on the core of it, and that decision is based on what it needs to do, obviously! Pis are good for certain stuff, very accessible and cheap. HOWEVER I am not convinced they are the best thing for control and monitoring purposes. The reason being they have a large and very complex (relatively) fast processor, and run under a linux-type operating system. In other words, there are huge overheads if what you want to do is relatively simple. Consequently you are never quite sure exactly what the processor is doing and the power consumption is high, which is an issue if you are not on shore power. They are way over -specced for many jobs. For more simple control and monitoring projects, I’d suggest looking at an Arduino. These are on a completely different level of complexity, you are much more in direct contact with the hardware and the power consumption is an order of magnitude less. i would only go for a Pi if you really need a sophisticated graphic display on a computer monitor/tv Was actually thinking of setting up and playing around at home on my pi 3, then transferring over to the raspberry pico OK but the pico is still a relatively powerful computer with an operating system, 2Mb of programme memory, 264kB of RAM and running at up to 133MHz (power consumption of CMOS devices is roughly proportional to speed) and uses up to about 100mA. By contrast the microprocessor im using for my alternator controller and Lithium battery BMS has 56kb of programme memory and 2.5 kB of RAM, and runs at 8MHz. So far I have not exceeded 30% RAM usage and about 50% programme memory. And they are doing some quite complicated stuff interfacing with various other things via CANbus, LIN, I2C, SPI, RS232. The current consumption is a few mA. Anyway, having said my piece on that, to answer your original question you use the GPIO pins on the Pi. However you need to make sure the Pi and whatever you are connecting to, are operating on the same io voltage. The Pi uses 3.3v but a lot of other stuff might use 5v, in which case you cannot connect the two directly, you need level shifters, onto-isolators etc
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Post by Telemachus on Jan 25, 2021 11:55:25 GMT
Ok but heed my point about peripheral voltage. If the GSM card etc runs on 5V then you can’t connect it directly to the Pi expansion board.
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Post by Deleted on Jan 25, 2021 12:08:56 GMT
The GSM card can be run on either 3.3v or 5v, 3.3v is default.
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Post by Telemachus on Jan 25, 2021 12:10:19 GMT
The GSM card can be run on either 3.3v or 5v, 3.3v is default. Ok that’s good. What about the other stuff you’re thinking of connecting?
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Post by Deleted on Jan 25, 2021 12:10:37 GMT
How would I convert mA into Ah?
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Post by JohnV on Jan 25, 2021 12:14:30 GMT
infinitessimally
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Post by Telemachus on Jan 25, 2021 12:14:50 GMT
How would I convert mA into Ah? Well 1mA for an hour is 1mAHour. 1mA for a day is 24mAh. 10mA for a day is 240mAh or roughly 1/4Ah. 100mA for day is 2.4Ah 100mA for a month is 72Ah. 100mA for a year is 864Ah This being my point earlier, quite a small drain of say 20mA isn’t really significant for a day, but if your boat is left a long time off shore power with no solar, it can mount up.
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Post by Deleted on Jan 25, 2021 12:21:59 GMT
Cheers.
Based on those figures, with the solar panel, I have no worries my batteries would be fine.
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