Can someone help me figure out what the unit of measure is for the 16 bit cumulative fuel counter at 0x0130 in the $8D (AUJP) mask? The code below takes the upper 16 bits of the 24 bit cumulative bpw counter at 0x012D, multiplies by 8 and saves at 0x0130. The math done to the upper 16 most significant bits has me confused. The units should still be injector on time, but how do I correlate the values in my log (over a time period) against the cumulative distance counter to find an accurate fuel economy value for that period?

<code>
ldd L012D ; RUN TIME TOTAL DELIVERED FUEL
lsld ; MULT * 2, MULT BY 8
lsld ; MULT * 2
lsld ; MULT * 2
std L0130 ; RUN TOTAL DELIVERED FUEL TO INST PNL
</code>

 

It looks to be that the contents of the address 0x12D are being divided by 32 and then stored/outputted to 0x130.

 

I don't think you've got that right. The LSLD opcode is Logical Shift Left Double.

example (8 bits)
0000 0100 (4 decimal)
..shift bits left by one position
0000 1000 (8 decimal)

The operation is a multiply by 2. If done three times, the result is mulitply by 8.

 

I said that because only the upper two bytes of the three byte (24 bit) value are used. Just by the face of things, this is equivelent to dividing by 256. Multiply by 8 and its a fast and crude way of dividing by 32. Is that the intention? Beats me. But what I see there with only the two uppermost bytes taken thats the conclusion Id draw.

 

I see what you are saying now... your right, the bigger picture is a divide by 32. Sorry about that.

 

edit: deleted incorrect information...

 

NP.