In SX Microcontrollers, SX/B Compiler and SX-Key Tool, johncouture wrote:

THE QUESTION:
 

I need to be able to set and get individual bit positions in a byte.  The SX/B help file says to do the following:

 

alarms         VAR     Byte(2)                 ' two bytes (16 bits)
fDoor          VAR     alarms(0).0             ' front door
bDoor          VAR     alarms(0).1             ' back door
patio          VAR     alarms(1).7


Using alarm as an example, I want to:

 

a = 1

x = 1

y = 7

alarm(x)    = $00  ' clear the 2nd byte (this works)

alarm(x).y  = a    ' to set the 8th bit position within the 2nd alarm byte with a one

 

The SX/B seems to imply that patio(1).7 has to be hard coded.  I need to be able to have variables in place of the 1 and the 7.

 

Does anyone know how to do it.

 

THE APPLICATION:

 

In working on the 1 Wire Search ROM routine, I need to store 64 bits of information.  A zero would indicate that there is no collision in this bit position and a one would indicate that there is a collision in this position.  This information will help in the next pass to determine which bits need to be toggled so that you can change your search pattern.

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