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E_Blue
Joined: 13 Apr 2011
Posts: 417
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| How to declare a bit from a variable.... |
 Posted: Wed Oct 12, 2022 9:18 pm |
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How to declare a bit from a variable that is inside of an Structure?
Example
| Code: |
struct Alarm_St1{
unsigned int8 ratioOne;
unsigned int8 ratioZero;
int1 ratioOV;
int1 NewPacketReady;
int1 ReadBits;
unsigned int8 TimerPacket;
unsigned int8 BitCount;
unsigned int32 LastPacket;
unsigned int8 LastData;
unsigned int8 LastCRC;
unsigned int8 CRC_result;
unsigned int8 CurrentPacket[6];
unsigned int8 CurrentData;
}Alarm;
#bit TamperX = DSC.CurrentData.0
unsigned int8 Dummy;
#bit DummyZero = Dummy.0
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DummyZero is ok but TamperX returns the following error
A numeric expression must appear here
I also tried adding some parentheses or brackets with similar results.
I want to able to do something like
| Code: |
if(TamperX)
{
Alarm();
TamperX=FALSE;
} |
_________________
Electric Blue |
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Ttelmah
Joined: 11 Mar 2010
Posts: 19520
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| Posted: Thu Oct 13, 2022 1:56 am |
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Use a union and if you want a short name, a define. So:
| Code: |
union bits {
unsigned int8 whole;
int1 bits[8];
};
struct Alarm_St1{
unsigned int8 ratioOne;
unsigned int8 ratioZero;
unsigned int8 TimerPacket;
unsigned int8 BitCount;
unsigned int32 LastPacket;
unsigned int8 LastData;
unsigned int8 LastCRC;
unsigned int8 CRC_result;
unsigned int8 CurrentPacket[6];
union bits CurrentData;
//comment here. You will find the compiler tends to prefer
//int1 declarations are done after other types.
int1 ratioOV;
int1 NewPacketReady;
int1 ReadBits;
}Alarm;
//You now have access to the bits in currentdata, as bits[0]..7
//give this a short name if required
#define TamperX Alarm.CurrentData.bits[0]
unsigned int8 Dummy;
#bit DummyZero = Dummy.0
void main()
{
//you can now test as a simple variable.
if (TamperX)
{
//do what you want
}
while(TRUE)
{
//TODO: User Code
}
}
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Note that since the location is fixed, the compiler optimises this totally, so
the test compiles as:
| Code: |
.................... if (TamperX)
0001E: BTFSS 15.0
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Where 'Alarm' here is stored in 0x4..0x16.
Note that what was CurrentData, is now CurrentData.whole |
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E_Blue
Joined: 13 Apr 2011
Posts: 417
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| Posted: Thu Oct 13, 2022 11:03 am |
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So, that way, is not needed to call bit_test function?
| Code: |
if(bit_test(TamperX))
{
} |
Also to compare Alarm.CurrentData with another 8 bit variable or value I must use
| Code: |
if(Alarm.CurrentData.whole==A5)
{
....
}
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_________________
Electric Blue |
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Ttelmah
Joined: 11 Mar 2010
Posts: 19520
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| Posted: Thu Oct 13, 2022 11:49 am |
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You were trying to declare a bit, so not using a bit_test.
Yes on using .whole.
If you are prepared to use bit_test, then you can just leave the data
declared as a byte not a union, and use bit_test on this. |
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E_Blue
Joined: 13 Apr 2011
Posts: 417
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| Posted: Thu Oct 13, 2022 1:27 pm |
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I got this error on CurrendData definition
Expecting a {
My compiler version is 5.091
_________________
Electric Blue |
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temtronic
Joined: 01 Jul 2010
Posts: 9229
Location: Greensville,Ontario
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| Posted: Thu Oct 13, 2022 1:47 pm |
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| Need to see the code..... |
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E_Blue
Joined: 13 Apr 2011
Posts: 417
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| Posted: Thu Oct 13, 2022 1:57 pm |
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The code is the same of Ttelmah made.
The whole code has around 22K lines and I'm not allowed to show it.
_________________
Electric Blue |
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Ttelmah
Joined: 11 Mar 2010
Posts: 19520
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| Posted: Fri Oct 14, 2022 1:32 am |
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The code I posted, with a suitable chip header, compiles as runs. It was
cut and pasted from my test.
Here you have posted CurrendData, not CurrentData. Are you sure you
haven't got some similar typo?. |
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E_Blue
Joined: 13 Apr 2011
Posts: 417
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| Posted: Fri Oct 14, 2022 10:36 am |
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Yes, there's not any typo in the code.
I just decided to declare the variables outside the struct.
| Code: | unsigned int8 CurrentData,LastData;
#bit Alarm_Tamper = CurrentData.0
#bit Alarm_Rest = CurrentData.1
#bit Alarm_BatErr = CurrentData.3
#bit Alarm_SenOpen = CurrentData.5
#bit Alarm_HearBit = CurrentData.6
#bit Alarm_OldTamper = LastData.0
#bit Alarm_OldRest = LastData.1
#bit Alarm_OldBatErr = LastData.3
#bit Alarm_OldSenOpen = LastData.5
#bit Alarm_OldHeartBit = LastData.6 |
_________________
Electric Blue |
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