Adding raw low / high byte debugging for wheel speeds

E46_debugging.lua

--This example configured for E46 CAN
-- Automatically starts logging with engine 'on' (RPM triggered)
--how frequently we poll for CAN messages
tickRate = 30
--the CAN baud rate
CAN_baud = 500000
--CAN channel to listen on. 0=first CAN channel, 1=second
CAN_chan = 0

--add your virtual channels here
--format addChannel(<name>, <sample rate>, <precision>, <min>, <max>, [units])
id339 = addChannel('brakesw_339', 10, 0, 0, 255)
id809 = addChannel('clutch_809', 10, 0, 0, 255)

function debug_339(data)
setChannel(id339, data[1])
end

function debug_809(data)
setChannel(id809, data[4])
end

----------------------------------------
--customize here for CAN channel mapping
--format is: 
--[CAN Id] = function(data) map_chan(<chan_id>, <data>, <CAN offset>, <CAN length>, <multiplier>,
--                                   <adder>, [filter])
----------------------------------------
CAN_map = {
[339] = function(data) debug_339(data) end,
[809] = function(data) debug_809(data) end,
}

function onTick()
    processCAN(CAN_chan)
end
--===========do not edit below===========
function processCAN(chan)
    local msg = 0
    repeat
        local id, e, data = rxCAN(chan)
        if id ~= nil then
            local map = CAN_map[id]
            if map ~= nil then
                map(data)         
            end
        end
        msg = msg + 1
    until id == nil or msg > 100
end

--Map CAN channel, little endian format
function map_chan(cid, data, offset, len, mult, add, filter)
    if offset + len > #data then return end
    offset = offset + 1
    local value = 0
    local shift = 1
    while len > 0 do
        value = value + (data[offset] * shift)
        shift = shift * 256
        offset = offset + 1
        len = len - 1
    end
 local cv = value * mult + add
 if filter ~= nil then cv = filter(cv) end
    setChannel(cid, cv)
end
initCAN(CAN_chan, CAN_baud)
setTickRate(tickRate)