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VRI_SetBaro.lua for M-Panel that respects FSX unit setting


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I just modified VRI_SetBaro.lua from "Example LUA plugins.zip" to use the unit setting in the general options of FSX instead of Lua flag 0 and thought it would be nice to share it.

Unrelated changes (yes, I know that one should not mix changes, but maybe you want them, too :)) are:

- replaced tabs with 2 spaces (otherwise existing indentation would be wrong)

- set my VRIdriver/VRIdevice ports when testing



-- VRInsight example: displays Inches or Millibars, by Pete Dowson, March 2010
-- adjusted to respect unit setting at offset 0C18, by Thomas Arendsen Hein, November 2011
-- Needs these filters:
-- WrFilter.1=BAR?
-- RdFilter.1=BAR?+

if VRImodel == nil then
-- Set known ports if testing with Lua not loaded automatically
VRIdriver = "COM6"
VRIdevice = "COM5"

speed = 115200 -- is this the same for all VRI devices?
handshake = 0 -- No handshake
minsize = 8
maxsize = 8 -- VRI seems to use fixed length blocks of 8 bytes

dev = com.open(VRIdevice, speed, handshake)

if dev == 0 then
ipc.log("Could not open VRIdevice port")

function setbarodisplay(off, val)
-- val is BARO setting in 16ths of millibar
if ipc.readUW(0xC18) > 0 then
-- need whole number of millibars
val = (val + 8) / 16 -- Note rounding by addition of 8
-- need to convert to 100ths of inch
val = ((val * 2992) / (1013.2 * 16)) + 0.5 -- note rounding
str = string.format("BAR%04d", val)
com.write(dev, str, 8)

function setbarovalue(handle, str)
-- need to check only for BARnnnn+/- and send correct millibars x 16 to FS
baro = tonumber(string.match(str, "BAR(%d%d%d%d)"))
if baro ~= nil then
if ipc.readUW(0xC18) > 0 then
-- metric, using millibars
baro = baro * 16 -- FS units are 16ths
-- using inches
baro = ((baro * 1013.2 * 16) / 2992) + 0.5 -- note rounding
ipc.writeUW(0x330, baro)


function unitchanged(off, val)
setbarodisplay(0x330, ipc.readUW(0x330))

unitchanged(nil, nil)

event.offset(0x330, "UW", "setbarodisplay")
event.offset(0xC18, "UW", "unitchanged")
event.VRIread(dev, "setbarovalue")

Same file as attachment for your convenience: VRI_SetBaro.lua.txt

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