Project 136: Thermal Imager Project Update 3: RAM Addon
by PhoenixGames on Sep.13, 2015, under Inventions
I have added some additional RAM to my arduino board. I need at least 4.8KB’s of RAM, and the Arduino Nano (and Atmel Atmega 328 chip) has only 2KB. I have added a Microchip 23k256 chip using a 3.3v/v logic level converter. I am running the chip off of the Nano’s 3.3v line, and using the logic level shifter to change the voltages of the data lines.
Wiring and programming this RAM chip turned out to be very easy. THESE directions, and the chip’s datasheet HERE proved to be all the information that I needed.
I am now using the int8_t data type to store my values. This datatype supports values from -128 and 127. The FLIR data module has a maximum temperature range of -40 to 80 C, so this is all the precision that I need. This is an 8 bit, or 1 byte, datatype, so I can store 4,800 data points using just 4.8 KBs. I can even use linear interpolation to double the effective resolution of the chip, from 80*60 (4800) to 160*120 (19200). This would use up 19.2 KB’s of RAM, I have 23KB’s available.
I am a little worried that I will run out of pins, since I still have to add the Display and the FLIR dev kit. If I run out of pins, I will have to use a shift register to add more, which will add complexity. I have looked into this however, and using a shift register does not seem to be as complex as I had initially thought.
