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How can I write an Offset value into a Lvar using Lua script

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could someone help me please?

I´m trying to write the value from an offset into a Lvar using a lua script in FSUIPC 6.

The task is to monitor an offset, e.g. the battery master switch, and when the value changes, writing the new value into my declarded local variable.

This would be needed for Lorbys Axis and ohs realizing an interactive voice checklist.

Axis and ohs only accepts Lvariables, no offsets. SimVars wouldn´t do as I´m using Project Magenta´s Boeing suite.

Following script unfortunately won´t do the job:


local Battery_on = {}
function Batteryswitch(offset, val)
                  if value == 1 then
                   ipc.writeLvar("Battery_on", 1)
                   ipc.writeLvar("Battery_on", 0)
event.offsetmask(0x281C, 1,"UB","Batteryswitch")  --- bit 0


What am I doing wrong?

Any help highly appreciated.

Thanks a lot in advance

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event.offsetmask(0x281C, 1,"UB","Batteryswitch")

You're using "UB" which is 1 byte. Offset 0x281C is 4 bytes. So you're only testing the first byte. This will always be 0 because the entire 4-byte offset only stores 0 and 1. The actual bit you want to test is in offset 0x281F.

You can with target that byte:

event.offsetmask(0x281F, 1,"UB","Batteryswitch")

or tell LUA read the full 4 bytes from the original offset with "UD" (unsigned double word)

event.offsetmask(0x281C, 1,"UD","Batteryswitch")

You don't really need to test the individual bit as only one bit is ever flipped - the entire offset value can only be 0 or 1.

So you could also use the plain event.offset function like this and test the entire value (0 or 1):



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