ELM327
Programmable Parameter Summary (continued)
PP
Description
Values
Default
Type
11
J1850 Break Signal monitor enable
(reports BUS ERROR if break signal duration limits are exceeded)
00 = ON
FF = OFF
00
D
(ON)
12
J1850 Volts (pin 3) output polarity
00 = invert
FF = normal
FF
R
(normal)
normal = Low output for 5V, High output for 8V
invert = High output for 5V, Low output for 8V
13
14
15
16
17
18
19
1A
1B
1C
Auto search time delay between protocols 1 & 2
setting = value x 4.096 msec
00 to FF
00 to FF
00 to FF
32
I
(205 msec)
ISO/KWP final stop bit width (provides P4 interbyte time)
setting = 98 + value x 64 µsec
50
D
D
R
D
I
(5.2 msec)
ISO/KWP maximum inter-byte time (P1), and minimum
inter-message time (P2). setting = value x 2.112 msec
0A
(21 msec)
Default ISO/KWP baud rate (AT IB default setting)
4800 baud can not be a default - set it with AT IB 48
00 = 96
FF = 10
FF
(10.4K)
ISO/KWP wakeup message rate (AT SW default setting)
setting = value x 20.48 msec
00 to FF
00 to FF
00 to FF
00 to FF
00 to FF
00 to FF
92
(2.99 sec)
Auto search time delay between protocols 4 & 5
setting = value x 4.096 msec
00
(no delay)
Delay after protocol 5 attempt during an automatic search, if
protocols 3 & 4 have not been tried. setting = value x 20.48 msec
62
I
(2.0 sec)
Protocol 5 fast initiation active time (TiniL)
setting = value x 2.5 msec
0A
D
D
D
(25 msec)
Protocol 5 fast initiation passive time (TiniH)
setting = value x 2.5 msec
0A
(25 msec)
ISO/KWP outputs used for initiation
b7 to b2: not used - leave set at 0
03
(00000011)
b1: L line (pin 22)
b0: K line (pin 21)
0: disabled 1: enabled
0: disabled 1: enabled
(if disabled, an output remains low during initiation)
1D
ISO/KWP P3 time (delay before sending requests)
Ave time = (value - 0.5) x 4.096 msec
00 to FF
0F
D
R
D
D
D
(59 msec)
21
Default CAN Silent Monitoring setting (for AT CSM)
CAN auto formatting (AT CAF default setting)
CAN auto flow control (AT CFC default setting)
CAN filler byte (used to pad out messages)
FF = ON
00 = OFF
FF
(ON)
24
00 = ON
FF = OFF
00
(ON)
25
26
00 = ON
FF = OFF
00
(ON)
00 to FF
00
ELM327DSI
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