The K-Series ECU can be configured to output a serial stream for a datalogger.
Note that only PRB calibrations support the serial output. PRB calibrations may be used in PNF, PRD, PRC and PND ECUs with re-tuning, but cannot be used in PRA ECUs.
Software Setting
| • | In KManager under Parameters, Multiplexer select the 'Datalogger Output' option. |
Electrical Specifications
| • | Pin E24 (SEFMJ), normally used for dashboard communication. This use of this pin for a serial output stream will result in the stock water temperature gauge and charge indicator being disabled. |
| • | 12V / 0V signal levels. The high signal level may follow battery voltage (ie 10 - 14 V) |
| • | Normal polarity (idle state is 12V). |
Serial Specifications
| • | 9600 bps or 115,200 bps (software selectable), 8 data, 1 stop, no parity. |
| • | Packets are sent at approx 20Hz (9600 bps) or 30Hz (115200 bps) |
| • | There is only one packet type |
Packet Description
| • | Words are send with most significant byte first. |
| • | The checksum is calculated as the byte sum of the packet subtracted from 0xFF. The byte sum of the packet, including the checksum, should be 0xFF. |
Byte |
Contents |
0 |
Identification byte (0x69) |
1 |
Speed (kph, LSB = 1 kph) |
2-3 |
Rpm (LSB = 0.25 rpm) |
4 |
Gear (0 - 6) |
5 |
ECT (degrees Celsius + 40, LSB 1 deg) |
6 |
IAT (degrees Celsius + 40, LSB 1 deg) |
7 |
Battery voltage (volts, LSB = 0.1V) |
8 |
TPS (0% = 0x15, 100% = 0xE5) |
9-10 |
MAP (mbar, LSB = 1 mbar) |
11-12 |
Injector duration |
13 |
Ignition timing (degs + 0x80, LSB = 0.5 deg) |
14 |
Output bit field |
15 |
Input bit field |
16 |
Cam angle (degrees + 40, LSB = 0.5 deg) |
17-18 |
Lambda (0x8000 = 1.00, LSB = 1/0x8000 lambda) |
19-20 |
Knock count (knocks since power on, LSB = 1 knock) |
21 |
Checksum |
Output bitfield
Bit |
Meaning |
0 |
Reverse lockout (1=on) |
1 |
Brake switch |
2 |
AC switch |
3 |
AC clutch |
4 |
SCS |
5 |
EPS/PSP |
6 |
Fuel pump |
7 |
Radiator fan |
Input bitfield
Bit |
Meaning |
0 |
VTEC oil pressure |
1 |
VTEC solenoid #1 |
2 |
VTEC solenoid #2 |
3 |
MIL |
4 |
Nitrous 1 arm |
5 |
Nitrous 2 arm |
6 |
Nitrous 1 active |
7 |
Nitrous 2 active |
Example output at 115,200 bps
Example packet 1
Byte |
Value |
Contents |
Meaning |
0 |
69 |
ID |
|
1 |
50 |
Speed |
80 kph |
2-3 |
022F |
Rpm |
559 rpm |
4 |
06 |
Gear |
6th |
5 |
69 |
ECT |
65 degrees C |
6 |
3F |
IAT |
23 degrees C |
7 |
86 |
Battery |
13.40 volts |
8 |
6D |
TPS |
42% |
9-10 |
0595 |
MAP |
1429 mbar |
11-12 |
0CAC |
Inj |
12.964 ms |
13 |
83 |
Ign |
1 degs BTDC |
14 |
41 |
Out |
RVSLK on, fuel pump on |
15 |
09 |
In |
VTEC pressure on, MIL on |
16 |
28 |
Cam |
0 degrees |
17-18 |
AFD9 |
Lam |
Lambda 0.728 (10.70:1) |
19-20 |
0000 |
Knk |
Knock count 0 |
21 |
A5 |
Check |
Packet byte sum = 0xFF |
Example packet 2
Byte |
Value |
Contents |
Meaning |
0 |
69 |
ID |
|
1 |
50 |
Speed |
80 kph |
2-3 |
0CE6 |
Rpm |
3302 rpm |
4 |
04 |
Gear |
4th |
5 |
82 |
ECT |
90 degrees C |
6 |
3F |
IAT |
23 degrees C |
7 |
86 |
Battery |
13.40 volts |
8 |
E4 |
TPS |
100% |
9-10 |
00327 |
MAP |
807 mbar |
11-12 |
079D |
Inj |
7.784 ms |
13 |
BC |
Ign |
30 degs BTDC |
14 |
41 |
Out |
RVSLK on, fuel pump on |
15 |
01 |
In |
VTEC pressure on |
16 |
28 |
Cam |
0 degrees |
17-18 |
AFD9 |
Lam |
Lambda 0.728 (10.70:1) |
19-20 |
0000 |
Knk |
Knock count 0 |
21 |
A9 |
Check |
Packet byte sum = 0xFF |
Notes:
| • | A working oxygen sensor is required to log the lambda. |
| • | Generally only one VTEC solenoid needs to be energized for the VTEC lobes to switch. |
| • | The gear may read 0 or 1 while stationary. |
| • | The gear ratios may be altered in KManager. |