ELM329
Programmable Parameter Summary (continued)
PP
Description
Values
Default
Type
2A
CAN Error Checking (controls testing)
00 to FF
08
D
(00001000)
Each bit of this byte controls an option, as follows:
b7: ISO 15765 Data Length
0: accept any 1: must be 8 bytes
Allows acceptance of non-standard data without errors.
b6: ISO 15765 PCI=00
0: allowed
1: not allowed
Some vehicles send 00’s, which can be confusing.
b5: reserved for future - leave set to 0
b4: reserved for future - leave set to 0
b3: Wiring Test
0: bypass
1: perform
Certain wiring conditions may cause problems. This allows
a quick test, which weeds out some problems.
b2: reserved for future - leave set to 0
b1: reserved for future - leave set to 0
b0: reserved for future - leave set to 0
2B
2C
Protocol A (SAE J1939) CAN baud rate divisor.
01 to 40
02
R
R
(250 Kbps)
The baud rate is determined by the formula:
rate (in kbps) = 500 ÷ value
For example, setting this PP to 19 (ie. decimal 25) provides
a baud rate of 500/25 = 20 kbps.
00 to FF
E0
Protocol B (USER1) CAN options.
(11100000)
Each bit of this byte controls an option, as follows:
b7: Transmit ID Length
b6: Data Length
0: 29 bit ID
1: 11 bit ID
0: fixed 8 byte 1: variable DLC
b5: Receive ID Length
b4: baud rate multiplier
(see note 2)
0: as set by b7 1: both 11 and 29 bit
0: x1
1: x 8/7
b3: reserved for future - leave set at 0.
b2, b1, and b0 determine the data formatting options:
b2 b1 b0
Data Format
none
ISO 15765-4
SAE J1939
0
0
0
0
0
1
0
1
0
Other combinations are reserved for future updates – results will
be unpredictable if you should select one of them.
2D
2E
Protocol B (USER1) baud rate divisor. See PP 2B for a description.
01 to 40
00 to FF
04
R
R
(125 Kbps)
Protocol C (USER2) CAN options. See PP 2C for a description.
E0
(11100000)
ELM329DSB
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