Problem Reading various Bool values

[acolvard]

I have created a program to interface with BetaInnovations Gammatron. I have one device that emulates the G1000 and everything is working fine. I have another device for switches like lights, deice, battery etc. which I am having some difficulty.

In my code I read some values for heading, kohlsman, nav radials and then use those to perform some processes. These work fine. I added several variables that are bools and they do not retrun the proper values. For example pitot heat is always false regardless of the switch position. I am using the no callback method. Here is some relevent code. Any Ideas?

struct Struct1
{
double headingn;
double kohlsmann;
bool pitotheatn;
};

hr = SimConnect_AddToDataDefinition(hSimConnect, DEFINITION_READ, "Heading indicator", "Degrees");
hr = SimConnect_AddToDataDefinition(hSimConnect, DEFINITION_READ, "Kohlsman setting MB", "Millibars");
hr = SimConnect_AddToDataDefinition(hSimConnect, DEFINITION_READ, "Pitot Heat", "Bool", SIMCONNECT_DATATYPE_FLOAT32);

hr = SimConnect_RequestDataOnSimObject(hSimConnect, REQUEST_READ, DEFINITION_READ, SIMCONNECT_OBJECT_ID_USER, SIMCONNECT_PERIOD_ONCE);

hr = SimConnect_GetNextDispatch(hSimConnect, &pData, &cbData);

case SIMCONNECT_RECV_ID_SIMOBJECT_DATA:
{
SIMCONNECT_RECV_SIMOBJECT_DATA *pObjData = (SIMCONNECT_RECV_SIMOBJECT_DATA*) pData;

case REQUEST_READ:
{
Struct1 *pS = (Struct1*)&pObjData->dwData;

 

[acolvard]

I had one of my professional business and robotics apllication programmers come in and look for me. We had it working in five minutes. The solution is to use doubles in the struct statement. Appearantly, bools are not recongnized properly in the SDK.

 

[Pete Dowson]

I had one of my professional business and robotics apllication programmers come in and look for me. We had it working in five minutes. The solution is to use doubles in the struct statement. Appearantly, bools are not recongnized properly in the SDK.

That's a bit wasteful. All BOOLeans are kept as 32-bit integers internally.

I think what is happening here is a mix up in understanding the difference between the UNITS of a value being returned, and how it is stored. The "Bool" part of the request merely specifies the units (like feet or metres elsewhere). The TYPE of the value returned is specified by the data type parameter.

You should define the data type for a "Bool" as "SIMCONNECT_DATATYPE_INT32", that is all.

In the example, it might have actually worked if the "SIMCONNECT_DATATYPE_FLOAT32" type requested actually matched the data type declared in the struct:

struct Struct1
{
double headingn;
double kohlsmann;
bool pitotheatn;
};

A C/C++ "bool" is an INT32, not a FLOAT32. In C/C++ you define FLOAT32 by "float", if that's what you really want, though obviously a floating point value for something which is either 0 or 1 is wasteful.

Regards

Pete

 

[acolvard]

Makes since and that was what we discovered. In my blind rage to solve this issue after several hours I did not even see the int32 type. That is why another set of eyes always works. Thanks.