3D VR Headset

Of course you first need to execute the commands to initialise the device. Then the PYR should work like this (assuming you have declared it in the decls)

my_pitch=createbank(4)
my_yaw=createbank(4)
my_roll=createbank(4)

Get_PYR(my_pitch, my_yaw, my_roll)
print peekint(my_pitch,0)
print peekint(my_yaw,0)
print peekint(my_roll,0)

as for the C++ code, it looks like everything is pretty simple to convert to blitz:

my_pitch=createbank(4)
my_yaw=createbank(4)
my_roll=createbank(4)


;// Start by connecting to the CyberMaxx
if AutoDetectComPort()=0
 ;// ERROR CyberMaxx not Found
 runtimeerror "ERROR CyberMaxx not Found"
endif

;// These are optional
;CyberHMD.SetHysteresisOn(); // turn on the hysteresis filter to minimize jittering (try this later)

my_version_adr=Get_Version%() ; returns a pointer to a string

SetSamplingRate(50); // Used only in continous mode
;// default is 40 packets/s

;// This is how you read
while keyhit(1)=0
 ;// if the CyberMaxx has supplied data, this returns true
 if  ReadFromPort()<>0
  Get_PYR(my_pitch, my_yaw, my_roll)
  print peekint(my_pitch,0)
  print peekint(my_yaw,0)
  print peekint(my_roll,0)
 else
  print "Error"
 endif
wend

Of course I doubt it will work right away, but probably it gives you the direction.

Again, make sure your decls are using the right function name return types, I see you have a lot of string return types, doublecheck if everything is right

void dothis() means it won't return anything
char dothis() means it will return a string. declare: dothis$()
char* dothis() means it will return a (32bit int) pointer to a string, use dothis%() (see below how to use a pointer)
int dothis() means it will return an int, use dothis%()
BOOL dothis() means it will return true or false, I think you can use an int here.

The function Get_Version is a bit special, it will return an adress (=Pointer) of a 10 Bytes string. You need to use RTLMemoryMove2 to copy the 10 bytes to a blitz bank. See code archives, userlibs, Avifil32 Frame grabber example on how to declare and use RTLMemoryMove.