Talk:Wishlist/Sensorbox

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(User:Hns)
("...The LPC214x series is the only ARM7® microcontroller family with full USB 2.0 compliance and USB.org certification...")
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** 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).
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*** Look e.g. on the cheap [http://www.standardics.nxp.com/products/lpc2000/lpc214x/ LPC214x] quote: "...The LPC214x series is the only ARM7® microcontroller family with full USB 2.0 compliance and USB.org certification..." (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).
 
***Test/development/production boards:
 
***Test/development/production boards:
 
****USB powered through USB-flash port, only mentions 2 ADC-ports: [http://www.embeddedartists.com/products/education/edu_2148.php embeddedartists.com: LPC2148 Education Board] (two USB ports - one for programming via a ftdi-chip(USB<->serial) - and one directly connected to LPC2148)
 
****USB powered through USB-flash port, only mentions 2 ADC-ports: [http://www.embeddedartists.com/products/education/edu_2148.php embeddedartists.com: LPC2148 Education Board] (two USB ports - one for programming via a ftdi-chip(USB<->serial) - and one directly connected to LPC2148)

Revision as of 15:46, 2 November 2008

Processor discussion


--Glenn 14:25, 2 November 2008 (UTC)

User: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 PIC16C765 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

PIC16C765 is a bad development platform, because it can only be programmed once (OTP). It is also not possible to update to newer enhanced firmware version for the same reason.

There is also:

But for almost the same or a little more, you get much more with ARM (e.g. LPC2144, LPC2148).

--Glenn 14:23, 2 November 2008 (UTC)

Personal tools

Processor discussion


--Glenn 14:25, 2 November 2008 (UTC)

User: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 PIC16C765 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

PIC16C765 is a bad development platform, because it can only be programmed once (OTP). It is also not possible to update to newer enhanced firmware version for the same reason.

There is also:

But for almost the same or a little more, you get much more with ARM (e.g. LPC2144, LPC2148).

--Glenn 14:23, 2 November 2008 (UTC)