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Post by silverdragon on Aug 31, 2015 10:06:11 GMT
Raspberries are great for doing one up type hombuilt projects. But if you need to build and sell a couple of thousand products a year, there are much cheaper alternatives. We do a lot of prototyping with raspberries, but then build our own hardware for production. Greg, what is it you do again?... (Being nosey?...) Also, yeah, having a full functioning micro is useful when doing the design work, you can diagnose the workings better. But in the finished product, do you need full keyboard and access to firefox and photoshop?... of course, you simplify the design to only do what is required.
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Post by GTCGreg on Aug 31, 2015 15:07:26 GMT
Raspberries are great for doing one up type hombuilt projects. But if you need to build and sell a couple of thousand products a year, there are much cheaper alternatives. We do a lot of prototyping with raspberries, but then build our own hardware for production. Greg, what is it you do again?... (Being nosey?...) Also, yeah, having a full functioning micro is useful when doing the design work, you can diagnose the workings better. But in the finished product, do you need full keyboard and access to firefox and photoshop?... of course, you simplify the design to only do what is required. My company makes HVAC and power distribution controls for emergency and military vehicles. Most of our products have used Microchip PIC processors but we are now switching over to ARMs. The Raspberries are nice because they are based on the ARM architecture and already have everything you need on a cheap development board. There is also a lot of open-source code available. Once we figure out what we DON'T need, we can often find much cheaper alternative boards to use for production that just have what we need on them. For example, we don't need wi-fi or the ability to drive a monitor or TV. We also don't need a flash card reader as all of our programs (so far) have been small enough to fit in the internal flash memory of the processors. BTW, we don't use any OS. No Windows, No Linux. Everything is compiled to straight assembly language, usually from C. That's how we manage to get it all to fit in the microprocessors internal flash.
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Post by silverdragon on Sept 1, 2015 4:12:44 GMT
Is Trend Sachwell Honeywell and Micro still in the market?... I spent may hours with Trend back in the days I did that stuff doing their particular flavour of control architecture. It was dial up between two modems time, before the internet. 1987/8/9 approx....
And yes, I can see immediately how a Raspberry would be useful. Even as an on-site diagnostic tool....
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Post by c64 on Sept 1, 2015 13:44:32 GMT
Is Trend Sachwell Honeywell and Micro still in the market?... I spent may hours with Trend back in the days I did that stuff doing their particular flavour of control architecture. It was dial up between two modems time, before the internet. 1987/8/9 approx.... And yes, I can see immediately how a Raspberry would be useful. Even as an on-site diagnostic tool.... The Raspberry is meant for educational purposes and very good at it. But for making products, it's not very good since it lacks important features. It doesn't come with a watchdog. When it crashes, someone needs to unplug and plug it back in to reboot. Then it has no BIOS and no firmware. When you plug it in, the GPU(!) starts looking for two files on the FAT formated partition of the SD card. First it examines the config.txt which is like BIOS settings. After configuring the Raspberry, the GPU then loads a binary of the firmware. This firmware is not open source. If the SD card fails, the Raspberry can't work at all. And it is very likely that either the Raspberry crashes writing the SD card and destroying the file system or the SD card itself fails from age, wear, EMC or other defects. Especially when the power is cut out of a sudden, the Raspberry may destroy its filesystem. So without someone able to replace the SD card or to reboot it, it may turn useless. That's why ou should use an Arduino (contains ARM µC) or a bare Microcontroller. The microcontroller has a built in ROM. It is very unlikely that the program in the ROM turns corrupt. And it contains a watchdog. If the µC crashes, it will restart fully automatically within a few seconds. You can cut the power any time without risk of destroying the firmware. In Greg's case, a simple and slow running 8-bit Microcontroller is more than enough to do the job. Using an AVR is a good choice since there is a vast library of program code for the Arduino you can use for your own projects, even without using an actual Arduino. The Arduino is based on an ATmega which is compatible to most Atmel micro controllers. If you need real processing power (like I currently need for my projects), you can always use an AVR32. The UC3 series runs with up to 66MHz and handles one instruction per clock cycle. This makes it even more powerful than a classic 500MHz PC. For an On-site diagnostic tool, you might want to look at the "Net IO" board from Pollin. This is a ATmega32 with a fake printer port, an RS232 and Ethernet controller. The Pollin software they offer isn't usefull at all, but there is the "Ethersex" project. Using this one, you can turn the Net IO into a powerful SNMP monitor.
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Post by GTCGreg on Sept 1, 2015 17:18:10 GMT
The Raspberry is meant for educational purposes and very good at it. But for making products, it's not very good since it lacks important features. It doesn't come with a watchdog. When it crashes, someone needs to unplug and plug it back in to reboot. Then it has no BIOS and no firmware. When you plug it in, the GPU(!) starts looking for two files on the FAT formated partition of the SD card. First it examines the config.txt which is like BIOS settings. After configuring the Raspberry, the GPU then loads a binary of the firmware. This firmware is not open source. If the SD card fails, the Raspberry can't work at all. And it is very likely that either the Raspberry crashes writing the SD card and destroying the file system or the SD card itself fails from age, wear, EMC or other defects. Especially when the power is cut out of a sudden, the Raspberry may destroy its filesystem. So without someone able to replace the SD card or to reboot it, it may turn useless. That's why ou should use an Arduino (contains ARM µC) or a bare Microcontroller. The microcontroller has a built in ROM. It is very unlikely that the program in the ROM turns corrupt. And it contains a watchdog. If the µC crashes, it will restart fully automatically within a few seconds. You can cut the power any time without risk of destroying the firmware. In Greg's case, a simple and slow running 8-bit Microcontroller is more than enough to do the job. Using an AVR is a good choice since there is a vast library of program code for the Arduino you can use for your own projects, even without using an actual Arduino. The Arduino is based on an ATmega which is compatible to most Atmel micro controllers. If you need real processing power (like I currently need for my projects), you can always use an AVR32. The UC3 series runs with up to 66MHz and handles one instruction per clock cycle. This makes it even more powerful than a classic 500MHz PC. For an On-site diagnostic tool, you might want to look at the "Net IO" board from Pollin. This is a ATmega32 with a fake printer port, an RS232 and Ethernet controller. The Pollin software they offer isn't usefull at all, but there is the "Ethersex" project. Using this one, you can turn the Net IO into a powerful SNMP monitor. Correct. In addition to the Raspberry, we do use an Arduino for development. The Arduino uses an ARM STM32 family processor which is the same processor used in the touch display/processor board we use for production. That uses an STM32F103 processor. I think I emailed you a picture of that display/processor setup a while back. The best part is the entire touch display and processor board only costs $17 in large quantities. Attachment Deleted
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Post by silverdragon on Sept 2, 2015 6:34:09 GMT
All Raspberry users are encouraged to make a backup file system as soon as possible, and make a second o/s card, just in case the first one fails.
Its a basic cheep computer, what were you expecting for less than £50. Its supposed to be "bare bones"
As it comes with 4port USB, you are kind of expected to keep anything important on external memory.
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Post by c64 on Sept 2, 2015 12:49:56 GMT
All Raspberry users are encouraged to make a backup file system as soon as possible, and make a second o/s card, just in case the first one fails. Its a basic cheep computer, what were you expecting for less than £50. Its supposed to be "bare bones" As it comes with 4port USB, you are kind of expected to keep anything important on external memory. It's not really a "basic cheap" computer at all. It is a computer where you don't pay extra for research and development and you don't pay extra for the brand and advertisements. The chip development was mostly paid for by the smartphone industry and the actual Raspberry development was done by the university of Cambridge. It is actually very expensive since they make it in the UK. If they would produce it in China, it would cost much less than $20! It is not meant to be reliable since it is for educational purposes. The average uptime until it crashes is much less than a month. You are lucky if it keeps working a week without a malfunction. A common PC has an average uptime until it malfunctions caused by hardware glitches of at least 10 months. So while a Raspberry is great for educational purposes, experimenting and DIY stuff, it is not suitable for office and industry applications. My dad had bought one for his home office. He has retired a long time ago and actually needs nothing more than a desk calculator and a typewriter for his office. Since you can't buy ink rollers for desk calculators and typewriter ribbons any more, his old TV, the Raspberry and his old HP 4L laserprinter is perfect for his purposes.
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