View Full Version : Teensy 3.1 Audio Shield FFT Problems

08-08-2014, 03:16 PM
Hi, i'm currently working on a micro audio solution. Most of the planned features are working but when i try to compile a version with FFT i always get this compiler error.

D:\Arduino_Build\fft\core.a(analyze_fft256.cpp.o): In function `AudioAnalyzeFFT256::update()':
D:\arduino-1.0.5\libraries\Audio/analyze_fft256.cpp:83: undefined reference to `arm_cfft_radix4_q15'
D:\Arduino_Build\fft\core.a(analyze_fft256.cpp.o): In function `AudioAnalyzeFFT256::init()':
D:\arduino-1.0.5\libraries\Audio/analyze_fft256.cpp:38: undefined reference to `arm_cfft_radix4_init_q15'
collect2.exe: error: ld returned 1 exit status

I'm using the i2c_t3 library instead of Wire, because i use 2 busses with different speed.

08-08-2014, 03:23 PM
Are you building in Arduino with Teensyduino, or with a non-Arduino makefile?

I'm guessing this is a non-Arduino build that isn't linking in the ARM math library.

08-08-2014, 03:35 PM
I'm using Arduino with Teensyduino but Subleme Text 2 as external editor.

08-08-2014, 04:26 PM
First, make sure you're using at least Teensyduino version 1.19. Use Arduino's Help > About menu to check. If you have an older version, upgrade to at least 1.19. Th

If so, use File > Prefernces to turn on verbose info while compiling. That extra info is needed to troubleshoot this issue. Arduino should give you a "copy error" button to easily copy the entire output to the clipboard. Best to paste it here inside "code" tags, since it'll be long.

08-08-2014, 05:12 PM
Found the issue, its the SublemeText plugin. It works in Arduino/Teensyduino.

01-05-2015, 10:04 AM
Was having the same issue using Eclipse Arduino plugin. Would compile in Arduino, but not in Eclipse.

Solved by adding -larm_cortexM4l_math to extra parameters to "combiner" in project properties, C/C++ Build, Settings, Arduino Combiner, Command Line Pattern. That's where I added it.

03-25-2015, 02:06 PM
@Kig, You sir are a champ!
Thanks to you I can compile with eclipse now instead of the horrible Arduino IDE!