[Eric Stage I]

Carl, your right, its the same range, but the 0-200% would be more feasible from a math point of view (I think even a 0-400% would be more feasible). It would be in 2% increments though. 200% would run a 72# injector up over 100% dc.

Doing the 16-bit multiply twice doesn't seem to be jiving. For example, starting with a PE A/F of 14.0, if I add 200% PE, I get a final A/F of 4.66. If I add 100% PE and do the 16-bit multiply twice, I get a final A/F of 3.52. Maybe I'm not doing it the way Dennis wanted.

Just curious, Carl, why the necessity to go below 0% if you no longer have to offset the TPS table? Do you want to go leaner than 13.5-14.0 A/F in PE? (Unless you have your PE A/F richer than that.)

Anyway,
I think this will work: ***EDIT: See Dennis's correction in a reply further down***

PE trim vs. RPM 0%-200% (17 value starting at 0 RPM)

3BAB: CE 35 6E LDX #$356E X = Fuel Trim vs. RPM (Percentage 0-200% in 2% increments)
3BAE: 96 19 LDAA $19 Load current RPM into A
3BB0: BD FC 09 JSR $FC09 Do table lookup
3BB3: 16 TAB B = A (Copy A to B)
3BB4: 4F CLRA A = 0 (Clear A)
3BB5: 05 ASLD D = D * 2 (Double it)
3BB6: C3 00 80 ADDD Add 128 to D
3BB9: DD 91 STD $91 FuelTrim = D
3BBA: 96 8F LDAA $8F Load PE A/F into A
3BBC: 7E 3C 29

I wish I could format that better.

Maybe Dennis could take a peek at that and see if it looks doable.


Eric