Cosworth CAN

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--Cosworth CAN bus integration

--how frequently we poll for CAN messages
tickRate = 30
--the CAN baud rate
CAN_baud = 1000000
--CAN channel to listen on. 0=first CAN channel, 1=second
CAN_chan = 0
--1 for Big Endian (MSB) mode; 0 for Little Endian mode (LSB)
be_mode = 1

--add your virtual channels here
tpsId = addChannel("TPS", 10, 0, 0, 100, "%")

--customize here for CAN channel mapping
--format is: [CAN Id] = function(data) map_chan(<channel id>, data, <CAN offset>, <CAN length>, <multiplier>, <adder>)
CAN_map = {
[256] = function(data) map_chan(tpsId, data, 7, 1, 1, 0) end
}

function onTick()
    processCAN(CAN_chan)
end

--===========do not edit below===========
function processCAN(chan)
    repeat
        local id, e, data = rxCAN(chan)
        if id ~= nil then
            local map = CAN_map[id]
            if map ~= nil then
                map(data)         
            end
        end
    until id == nil
end

--Map CAN channel, little endian format
function map_chan_le(cid, data, offset, len, mult, add)
    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
    setChannel(cid, (value * mult) + add)
end

--Map CAN channel, big endian format
function map_chan_be(cid, data, offset, len, mult, add)
    offset = offset + 1
    local value = 0
    while len > 0 do
        value = (value * 256) + data[offset]
        offset = offset + 1
        len = len - 1
    end
    setChannel(cid, (value * mult) + add)
end

map_chan = (be_mode == 1) and map_chan_be or map_chan_le
initCAN(CAN_chan, CAN_baud)
setTickRate(tickRate)