Talk:Wishlist/Sensorbox
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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. | ||
| − | Using an ARM processor just to convert some samples per second into USB appears to be overkill to me. But | + | Using an ARM processor just to convert some samples per second into USB appears to be overkill to me. 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 wouldbe better. |
| + | |||
| + | So what we need: | ||
| + | * single chip | ||
| + | * supports USB and approx. 8 ADC channels without many external components | ||
| + | * low power | ||
| + | * readily available development tools | ||
Revision as of 16:01, 2 November 2008
Processor discussion
A
- Please use the ARM processor (32bit address space) - it has no Bank switching; ARM has a big linear directly addressable memory. Can get flashed by this open source tool: lpc21isp, yahoo download (after user registration).
- Look e.g. on the cheap LPC214x (LPC2144-LPC2148 has 14 ADC multiplexed channels - two internal ADCs). Chip price: digikey.com: LPC2144 US$ 8.4, LPC2148 US$ 11.2. The 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:
- USB powered through USB-flash port, only mentions 2 ADC-ports: embeddedartists.com: LPC2148 Education Board (two USB ports - one for programming via a ftdi-chip(USB<->serial) - and one directly connected to LPC2148)
- ARM MP3/AAC Player Quote: "...This is my MP3/AAC player project. The difference to most other players is that decoding is not done on a specialized IC (like VS1001), but directly on the microcontroller. It can play MP3 (all bit rates) and AAC (up to ~256 kbps) from SD card in real time. The project is work in progress..."
- LPC2148-based Line-tracing Race Car Robot Kit
- ARM7 LPC2148 mini board, ARM7-Base development board for LPC2148
- ARM1136JF-S-based: buglabs.net, Some applications, bugcommunity wiki
- Gumstix
- AT91SAM7S256 (ARM) based: Lego Mindstorms NXT, NXT Programming Software
- Alekto; DIN RAIL mountable
- Atmel AT91SAM7X256 based (also ARM): Controller Board Overview, makingthings.com, sourceforge.net: makingthings
- Open source support:
- Links:
- Please use the ARM processor (32bit address space) - it has no Bank switching; ARM has a big linear directly addressable memory. Can get flashed by this open source tool: lpc21isp, yahoo download (after user registration).
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. 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 wouldbe better.
So what we need:
- single chip
- supports USB and approx. 8 ADC channels without many external components
- low power
- readily available development tools
