Talk:Wishlist/Sensorbox

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= Processor discussion =
 
= Processor discussion =
== A ==
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== N.N. ==
 
** Please use the ARM processor (32bit address space) - it has no [http://en.wikipedia.org/wiki/Bank_switching Bank switching]; ARM has a big linear directly addressable memory. Can get flashed by this open source tool: [http://tech.groups.yahoo.com/group/lpc21isp/ lpc21isp], [http://groups.yahoo.com/group/lpc21isp/files/ yahoo download (after user registration)].
 
** Please use the ARM processor (32bit address space) - it has no [http://en.wikipedia.org/wiki/Bank_switching Bank switching]; ARM has a big linear directly addressable memory. Can get flashed by this open source tool: [http://tech.groups.yahoo.com/group/lpc21isp/ lpc21isp], [http://groups.yahoo.com/group/lpc21isp/files/ yahoo download (after user registration)].
 
*** Look e.g. on the cheap LPC214x (LPC2144-LPC2148 has 14 ADC multiplexed channels - two internal ADCs). Chip price: [http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=568-1763-ND digikey.com: LPC2144 US$ 8.4], [http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=568-1765-ND LPC2148 US$ 11.2]. The [http://en.wikipedia.org/wiki/ARM_architecture ARM architecture] is "old" (from 1983), wildly known, used, efficient(high mips/watt) and uses low power (different kind of deep sleep).
 
*** Look e.g. on the cheap LPC214x (LPC2144-LPC2148 has 14 ADC multiplexed channels - two internal ADCs). Chip price: [http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=568-1763-ND digikey.com: LPC2144 US$ 8.4], [http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=568-1765-ND LPC2148 US$ 11.2]. The [http://en.wikipedia.org/wiki/ARM_architecture ARM architecture] is "old" (from 1983), wildly known, used, efficient(high mips/watt) and uses low power (different kind of deep sleep).
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****[http://www.computer-solutions.co.uk/info/Embedded_tutorials/usb_tutorial.htm Embedded USB - a brief tutorial]
 
****[http://www.computer-solutions.co.uk/info/Embedded_tutorials/usb_tutorial.htm Embedded USB - a brief tutorial]
 
****[http://bas.woodpecker.gotdns.org/ALDS.php ALDS]
 
****[http://bas.woodpecker.gotdns.org/ALDS.php ALDS]
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== Users:hns ==
 
== Users:hns ==
 
This is what has been thought of: a simple processor that still suppports A/D converters and USB. A good candidate appears to be http://ww1.microchip.com/downloads/en/DeviceDoc/41124c.pdf Cost is approx. 5 USD.
 
This is what has been thought of: a simple processor that still suppports A/D converters and USB. A good candidate appears to be http://ww1.microchip.com/downloads/en/DeviceDoc/41124c.pdf Cost is approx. 5 USD.

Revision as of 15:04, 2 November 2008

Processor discussion

N.N.

Users:hns

This is what has been thought of: a simple processor that still suppports A/D converters and USB. A good candidate appears to be http://ww1.microchip.com/downloads/en/DeviceDoc/41124c.pdf Cost is approx. 5 USD.

Using an ARM processor just to convert some samples per second into USB appears to be overkill to me on first though. But the PIC is just one of the options to considered. A drawback appears that the ADC resolution is just 8 bit. This is quite coarse for some sensors. 12 bit would be better...

So what we need:

  • single chip
  • supports USB and approx. 8 ADC channels without many external components
  • low power
  • readily available development tools
Personal tools

Processor discussion

A

Users:hns

This is what has been thought of: a simple processor that still suppports A/D converters and USB. A good candidate appears to be http://ww1.microchip.com/downloads/en/DeviceDoc/41124c.pdf Cost is approx. 5 USD.

Using an ARM processor just to convert some samples per second into USB appears to be overkill to me on first though. But the PIC is just one of the options to considered. A drawback appears that the ADC resolution is just 8 bit. This is quite coarse for some sensors. 12 bit would be better...

So what we need:

  • single chip
  • supports USB and approx. 8 ADC channels without many external components
  • low power
  • readily available development tools