@fifty60, the Photon/Electron memory map (flash) is:
- Bootloader (16 KB)
- DCT1 (16 KB), stores Wi-Fi credentials, keys, mfg info, system flags, etc…
- DCT2 (16 KB), swap area for DCT1
- EEPROM emulation bank 1 (16 KB)
- EEPROM emulation bank 2 (64 KB)
- System firmware (512 KB) [256 KB Wi-Fi/comms + 256 KB hal/platform/services]
- Factory backup, OTA backup and user application (384 KB) [3 x 128 KB]
With all those pieces loaded, there is approx 125KB of user flash and 60KB of user RAM available. It is important to note that MANY of the conventional Arduino libraries are already included in the Particle system firmware (wifi, SPI, I2C, TCP/UDP, etc.). This makes the user app “thinner”.