4 replies to this topic

[David Ditto]

To Everyone, I am a newbie to electronics and elementary at programming. I got my new Netduino Plus and I am wondering after "Hello World" if it is possible to request a health check from the Netduino and only Blink the LED if the Health Check is good. I am also wondering if the program size limit imposed by the microcontrollers memory size can be extended by writing code both to the chip and an SD card. Would the Micro-controller be able to access the main program from memory and DLLs or Drivers from the SD card? Just in case it helps to know the project that I am working, I am trying to program a telemetry type program that will first query all the chips to make sure they are healthy, and then query the chips to provide a GPS - Axis - Altitude report at Near Space altitudes.

[hanzibal]

As of now, it's not possible to write to flash from a program running on the Netduino. But there is talk of implementing this in future firmware releases.

See this thread where the topic is discussed further:

http://forums.netdui...o-flash-memory/

This is a sought for feature that would make it possible to save config data between power cycles.

[ErikN]

Is this a good breakdown of what you're asking?

• Can you request a health check from the Netduino?
• Can you extend the program memory size by using an SD card?

For 1, you can do a few things in an attempt to determine if your board is GO/NOGO but I don't know of any single or set of commands you can run to get this answer directly. For instance, I know of no way to say: Check analog pins can input and output relative to Aref correctly, check the onboard LED is functioning, etc. You'd have to identify the components critical to your operation and devise a way to do a system check yourself. When you do this you might find some things can't be tested when the board is connected to your circuit(s) and require a dedicated testing station. You might also find not every test can be run and understood by the board - for instance generating PWM might be hard to measure to ensure you're getting the correct frequencies and you'll need to use an external device to do the proper capture and/or analysis.

As for 2, there are a number of discussions on using the SD card as storage space for DLLs but keep in mind, once you load the DLL into memory, you're using the chip memory. You can't execute program space from the SD card directly. The SD card is primarily used to store log or resource files. I wouldn't count on being able to use this when decided on what boards to evaluate for your needs.

Side note: all consumer GPS receivers (sold in the US? made in the US? required by license?) have an arbitrary maximum operating altitude above which they will be unusable. Just something to be aware of when designing your project.

[David Ditto]

"Side note: all consumer GPS receivers (sold in the US? made in the US? required by license?) have an arbitrary maximum operating altitude above which they will be unusable. Just something to be aware of when designing your project." The DOD requiurement for the arbitrary maximum is 60K FT Altitude + 1K FtPS Speed. However most manufactures write the firmware code as 60K FT or 1 ftPS instead of 60KFT and 1 ftPS. My team and I have posted emails to a few of the larger chip makers with what we are trying to do in an effort to get a properly coded GPS Chip that will meet our needs.

[ErikN]

The DOD requiurement for the arbitrary maximum is 60K FT Altitude + 1K FtPS Speed. However most manufactures write the firmware code as 60K FT or 1 ftPS instead of 60KFT and 1 ftPS.

My team and I have posted emails to a few of the larger chip makers with what we are trying to do in an effort to get a properly coded GPS Chip that will meet our needs.

Sounds like you've got it covered then!