The Arduino boards both have a very limited amount of RAM. For the probe to be able to save data from the instruments for an uplink, nonvolatile storage is necessary. For this function, I selected some 1 megabyte SPI flash chips from Adafruit.
Here is the vendor link: flash
Here is the datasheet: W25Q80BV
The features of this part include:
- 8 pin DIP package
- 3.3 volts (needs shifters for 5 volt usage)
- SPI interface
- 1megabyte capacity
- 4 ma power consumption
I have not yet tested this part.