Value gets to 1 as expected 
Thank you VB6 and SpacePilot
Moderator: Moderators
// Current Implemenation of Reading Hid Report Axis Data
Private Function GetAxisData(Value As Byte, MSB As Byte) As Long
Select Case MSB
Case 0:
GetAxisData = -Value
Case 1:
GetAxisData = -(Value + 255)
Case 255:
GetAxisData = 255 - Value
Case 254:
GetAxisData = 512 - Value
End Select
End Function
Maybe it could be speed up a bit by passing a 2Byte Integer to read both Values Simultaneously and then do some Byte swapping Magic
If someone got a better solution would be nice to post here thx
Private Function GetAxisData(Value As Byte, MSB As Byte) As Long
Select Case MSB
Case 0:
GetAxisData = -Value
Case 1:
GetAxisData = -(Value + 255)
Case 255:
GetAxisData = 255 - Value
Case 254:
GetAxisData = 512 - Value
End Select
End Function
Maybe it could be speed up a bit by passing a 2Byte Integer to read both Values Simultaneously and then do some Byte swapping Magic
If someone got a better solution would be nice to post here thx
I don't know what you mean by reportbuffers 5/6....oh and now I see your new code. You should be able to do this with normal VB math.
You get translation and rotation values separately. Each will arrive in a 7 byte packet. The first byte indicates which type of packet you have. 1 indicates a translation packet. 2 indicates a rotation packet. (3 indicates a button packet).
The sample translatation packet then would be:
0 LSBX MSBX LSBY MSBY LSBZ MSBZ
Where LSBX is the Least Significant Byte of the X value and MSBX is the Most Significant Byte of the X value.
The MSB is 0 until you fill up the LSB. Then the extra bits are put into the MSB. E.g.,
__MSB______LSB__
|________|111111111| then add 1:
|_______1|_________|
The latter representing a 16-byte value 0000000100000000
Etc. You can get your compiler to do the combination of the bytes into a signed integer for you. You have to make sure negative numbers are done correctly by the syntax you construct. The negative numbers are twos-complement.
This is usually as simple as:
value = (MSB*256) + LSB
Often explicit casting is required to get the sign bit extended properly. I think that's what your code is in effect doing. You can't just look at one bit in the MSB though. The end user can scale that value up past 350-ish.
I don't know what the syntax is in VB. Judicious diagnostic printing will get you there.
You get translation and rotation values separately. Each will arrive in a 7 byte packet. The first byte indicates which type of packet you have. 1 indicates a translation packet. 2 indicates a rotation packet. (3 indicates a button packet).
The sample translatation packet then would be:
0 LSBX MSBX LSBY MSBY LSBZ MSBZ
Where LSBX is the Least Significant Byte of the X value and MSBX is the Most Significant Byte of the X value.
The MSB is 0 until you fill up the LSB. Then the extra bits are put into the MSB. E.g.,
__MSB______LSB__
|________|111111111| then add 1:
|_______1|_________|
The latter representing a 16-byte value 0000000100000000
Etc. You can get your compiler to do the combination of the bytes into a signed integer for you. You have to make sure negative numbers are done correctly by the syntax you construct. The negative numbers are twos-complement.
This is usually as simple as:
value = (MSB*256) + LSB
Often explicit casting is required to get the sign bit extended properly. I think that's what your code is in effect doing. You can't just look at one bit in the MSB though. The end user can scale that value up past 350-ish.
I don't know what the syntax is in VB. Judicious diagnostic printing will get you there.