No Unity output from SAMD21 with SerialUSB

PlatformIO Core
1

Hi,

Serial on my SAMD21 (Sodaq One) is hardware and the main console is SerialUSB

As such, pio test with unity just hangs with no output. (it is running, as I can blink in setup etc)

I’ve tried to create alternate implementations to drive the serial port output (for example)

#include "unity_config.h"

void unityOutputStart()
{
    SerialUSB.begin(115200);
}

But This won’t compile:

test/unity_config.c: In function 'unityOutputStart':
test/unity_config.c:7:5: error: 'SerialUSB' undeclared (first use in this function)
     SerialUSB.begin(115200);

It seems like the board variant (or something, I’m guessing at terminology here) isn’t brought into the test sources.

Thanks for any pointers

2

SerialUSB is a C++ object. You can’t directly access that from a .c file. You should rename it to unity_config.cpp and give all wanted Unity C functions their C name linkage with

extern "C" void unityOutputStart() {
//..
}

Note that redefining unityOutputStart() alone is not sufficient, ther are still read, flush, end functions etc to implement (the last of which should be a NOP so that the USB port doesn’t disappear)

3

Max,
Thank you for the great advice.

Firstly, yes I appreicate all the wanted untity functions - I ommitted the rest for brevity.

May I ask for another pointer?

After your suggestion of renaming to unity_config.cpp and adding the C linkage name, I get:

test/unity_config.cpp: In function 'void unityOutputStart()':
test/unity_config.cpp:5:18: error: conflicting declaration of 'void unityOutputStart()' with 'C' linkage
 extern "C"  void unityOutputStart()
                  ^~~~~~~~~~~~~~~~
In file included from test/unity_config.cpp:3:0:
test/unity_config.h:231:6: note: previous declaration with 'C++' linkage
 void unityOutputStart();
      ^~~~~~~~~~~~~~~~

Otherwise, If I drop the C linkage name from the cpp implemntation, I get what I think are linker errors:

.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o): In function `UnityPrintNumberUnsigned':
unity.c:(.text.UnityPrintNumberUnsigned+0x28): undefined reference to `unityOutputChar'
.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o): In function `UnityPrintNumber':
unity.c:(.text.UnityPrintNumber+0x8): undefined reference to `unityOutputChar'
.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o): In function `UnityPrintNumberHex':
unity.c:(.text.UnityPrintNumberHex+0x2c): undefined reference to `unityOutputChar'
.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o): In function `UnityPrint.part.0':
unity.c:(.text.UnityPrint.part.0+0x14): undefined reference to `unityOutputChar'
unity.c:(.text.UnityPrint.part.0+0x22): undefined reference to `unityOutputChar'
.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o):unity.c:(.text.UnityPrint.part.0+0x30): more undefined references to `unityOutputChar' follow
.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o): In function `UnityConcludeTest':
unity.c:(.text.UnityConcludeTest+0x1c): undefined reference to `unityOutputFlush'
.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o): In function `UnityFail':
unity.c:(.text.UnityFail+0x2e): undefined reference to `unityOutputChar'
unity.c:(.text.UnityFail+0x64): undefined reference to `unityOutputChar'
unity.c:(.text.UnityFail+0x72): undefined reference to `unityOutputFlush'
.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o): In function `UnityBegin':
unity.c:(.text.UnityBegin+0x1a): undefined reference to `unityOutputStart'
.pio/build/sodaq_one/liba57/libUnity.a(unity.c.o): In function `UnityEnd':
unity.c:(.text.UnityEnd+0x4): undefined reference to `unityOutputChar'
unity.c:(.text.UnityEnd+0x10): undefined reference to `unityOutputChar'
unity.c:(.text.UnityEnd+0x3c): undefined reference to `unityOutputChar'
unity.c:(.text.UnityEnd+0x50): undefined reference to `unityOutputChar'
unity.c:(.text.UnityEnd+0x54): undefined reference to `unityOutputFlush'
unity.c:(.text.UnityEnd+0x58): undefined reference to `unityOutputComplete'

I don’t have enough C++ experience to get this gonig so I’m grateful of your help.

Thanks

Rob

4

Then that header file is missing an

#ifdef __cplusplus
extern "C" {
#endif

// all functions

#ifdef __cplusplus
}
#endif

block