TRANSMISSION GP-DIRECT DRIVE 8P0439 - Caterpillar

    $24     Unit number 24    
6, 7     $0040     PID    
8, 9     $0E10     Data (1800 rpm, 3600 x 0.5 (scale x factor) = 1800 rpm)    
10     $03     Checksum    
Refer to Table 60 below.
Table 60
3. The following is an example of reading a sub listed parameter.    
Code Example    
500024050024D000484B    
Byte Position     Byte Contents     Description    
1 - 2     $5000     Preamble    
3     $24     IID    
4     $05     Number of bytes (except checksum) in this message after this byte    
5     $00     Flag
Bit 1
0 = ASCII    
6     $24     Unit number 24    
7 - 9     $D00048     PID (Cylinder number 9 ignition timing)    
10     $4B     Checksum    
Refer to Table 61 below.
Table 61
4. Read response.    
Code Example    
5001250624D00048000048    
Byte Position     Byte Contents     Description    
1 - 2     $5001     Preamble    
3     $25     IID    
4     $06     Number of bytes (except checksum) in this message after this byte    
5     $24     Unit number 24    
6 - 8     $D00048     PID    
9, 10     $0000     Data (0 degrees)    
11     $48     Checksum    Write Request and Response
Refer to Table 62 below.
Table 62
1. Send a write request.    
Code Example    
5000340600240047012CDE    
Byte Position     Byte Contents     Description    
1 - 2     $5000     Preamble    
3     $34     IID    
4     $06     Number of bytes (except checksum) in this message after this byte    
5     $00     Flag
Bit 1
0 = ASCII    
6     $24     Unit number 24    
7, 8     $0047     PID for desired engine timing    
9, 10     $012C     Desired Engine Timing    
11     $DE     Checksum    
Refer to Table 63 below.
Table 63
2. Look for the response    
Code Example    
50013505240047012CDD    
Byte Position     Byte Contents     Description    
1 - 2     $5001     Preamble    
3     $35     IID    
4     $05     Number of bytes (except checksum) in this message after this byte    
5     $24     Unit number 24    
6, 7     $0047     PID    
8, 9     $012C     Desired Engine Timing    
10     $DD     Checksum    
Refer to Table 64 below.
Table 64
3. Send the Write Request.    
Code Example    
500034070024D100A00C00D4    
Byte Position     Byte Contents     Description    
1 - 2     $5000     Preamble    
3     $34     IID    
4     $07     Number of bytes (except checksum) in this message after this byte    
5     $00     Flag
Bit 1
0 = ASCII
1 = Binary    
6     $24     MID    
7 - 9     $D100A0     PID (oxygen feedback feature enable)    
10, 11