TECHNICAL NOTES ON THE EEC-IV MCU - Auto diagnostics

Converting to decimal and dividing by 4:
21 23 26 28 31 34 39 56
12 ...
5 ...
4 ...
2 ...
1.5 1.5 2 3 4.5 8 12 20
1.5 1.5 2 3 4.5 8 12 18
The rows are stored last first, so reversing rows gives the table as displayed:
---------------
2) Function Tables
---------------
1.5 1.5 2 3 4.5 8 12 18
1.5 1.5 2 3 4.5 8 12 20
2 ...
4 ...
5 ...
12 ...
21 23 26 28 31 34 39 56
Eectch98-Part2.fm
The second of the two kinds of tables is identified in the output with ’func’ in the second line of
output for it. For example, the ’WOT Spark Advance vs. RPM’ table is:
"WOT Spark Advance vs. RPM
"func:29956,32,2,d4,0,2,d4,1
RPM:0,1000,1800,2150,2600,3500,5000,16383.75
WOT Spark Advance Deg TDC:10.25,10.25,22.25,25.75,26.75,26.75,30.25,30.25
"end
--The first line is the title of the table
--The second line is decoded as follows:
func -- identifies this as a function type table
29956 -- the decimal location of the table in the PROM
(or 7504 hex)
32 -- the total number of bytes in the table
2 -- the number of bytes in each X entry
d4 -- the scale of each X entry. In this case, divide
each X entry by 4 to get RPM
’m’ can be used to specify ’multiply each X entry’.
0 -- each X entry is unsigned
2 -- the number of bytes in each Y entry
d4 -- the scale of each Y entry. In this case, divide
each Y entry by 4 to get degrees of Spark Advance
’m’ can be used to specify ’multiply each Y entry’.
1 -- each Y entry is signed
From the binary:
007500 FF FF 79 00-20 4E 79 00 B0 36 6B 00
007510 A0 28 6B 00 98 21 67 00-20 1C 59 00 A0 0F 29 00
007520 00 00 29 00
Since each entry is 2 bytes long, group into pairs:
FF FF FF FF
79 00 00 79
20 4E 4E 20
79 00 00 79
B0 36 36 B0
6B 00 Since this is an Intel ---> 00 6B
A0 28 CPU, reverse bytes of ---> 28 A0
6B 00 each integer. ---> 00 6B
98 21 21 98
67 00 00 67
20 1C 1C 20
59 00 00 59
EEC-IV Technical Notes: Software 44 last edited: 9/29/98