QFAC project not backwards compatible with QFAA?

[Oliver]

Working on my first project in mbed using the Nordic nrf51-dk.

The project utilises a TMP112 temperature sensor and attaches the reading to the service data to make it available over BLE (using SoftDevice). I have had success getting things running on the nrf51-dk, and porting over to a custom board using the QFAC chip. However, due to supply issues, the other boards have QFAA chips on.

Frustratingly the compiled hex will run on the other board, but does not seem to read the I2C bus. Any ideas around this?

[Turbo J]

The QFAA chips have only 16KB of RAM according to the PS but the QFAC have 32KB. You may need to recompile your project to account for that.

If it is really the I2C then I recommend looking at the waveforms with an oscilloscope (and not a logic analyser) because any mistake with the pullup resistors breaks the bus.

[Knut Auvor Grythe]

I converted some build files from pca10028 (AKA QFAC) to pca10001 (AKA QFAA), both using s130 and SDK 12.3.0, and wrote this script to convert a folder of build files: github.com/.../nrf-pca10028-to-pca10001

If you don't have a Linux system to run the script on, the most important part is the memory values, as Torbo J mentions. Most of the other stuff should be identical between pca10028 and pca10001, except for stuff like the amount of LEDs and defines for Arduino ports. For the nRF5 SDK version 12.3.0, I've found you need to make the following changes to the RAM areas when using S130 version 2.0.1. If you're using S110 these values will probably be different.

Values for SDK version 12.3.0 with S130 version 2.0.1:

• RAM start: 0x20001870 -> 0x20001fe8
• RAM size: 0x6790 -> 0x2018 (used by Keil and GCC)
• RAM end: 0x20007fff -> 0x20003fff (used by IAR)

[Oliver]

Does this work for the hex files build in mBed?

[Knut Auvor Grythe]

I don't know, I've never used mBed. I'd expect the values to be the same, though, so you could give it a shot. Take a backup, change the values (either using the script or by hand), see what happens :-)