Talk:Wishlist/Sensorbox

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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 versions 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). PS: LPC214x quote: "...The LPC214x series is the only ARM7® microcontroller family with full USB 2.0 compliance and USB.org certification..."

--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 versions 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). PS: LPC214x quote: "...The LPC214x series is the only ARM7® microcontroller family with full USB 2.0 compliance and USB.org certification..."

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