Manual

Programming Manual

ECUSIMPMB www.obdsol.com 11 of 13

5.0 Examples

5.1 Creating a Basic ECU

In this example, we will create a basic custom ECU. This ECU will use the J1850 PWM protocol and support one PID (RPM).

Notes:

 After any reset, the simulator automatically creates default ECUs. Therefore, the first step is to delete the default

ECUs.

 The knobs are assigned to the first three ECUs (IDs $0, $1, and $2). We want to set the RPM to a fixed value,

therefore we will use the next available ID ($3).

Here is the complete list of commands:

SP 1 set the simulator’s protocol to PWM

EDA delete all existing (default) ECUs

EA 3 create ECU #3

EN 3, “My ECU” specify ECU name

EAP 3, 10 assign ECU physical address $10

EAF 3, 6A assign ECU functional address $6A

EP 3, 1 set ECU’s protocol preset to PWM

PA 3, 0C, 0FA0 create PID (RPM) and set its value to 1000 r/min

E 3, on turn on the ECU

Send the EL (“list ECUs”) command to verify that the ECU has been created correctly. You should see the following

summary:

3 My ECU 10,6A

We can now request RPM to verify proper operation. Commands below assume that you’re using an STN11xx-based OBD

tester (e.g., OBDLink SX or OBDLink MX):

>ATSP 1 set protocol to PWM

>ATH 1 turn on message headers

>01 0C send a request for RPM

41 6B 10 41 0C 0F A0 DE response from ECUsim

5.2 Adding PIDs

Previous example already demonstrated how to add the PID for RPM ($0C). However, most OBD testers would not be

able to read out the RPM value, or even connect to the ECU, because the ECU will not respond to a PID $00 request. There

are two ways to remedy this problem: either add the PID manually using the PA command, or use the PAUS command to

have the ECU automatically create and update the “supported PIDs” PIDs ($00, $20, $40, etc) on as-needed basis.

We’ll use the PAUS command in this example, as we add PIDs for vehicle speed and fuel level. Assuming you’ve already

set up a basic ECU from the previous example, enter the following commands:

PAUS 3, on enable auto-update of supported PIDs

PA 3, 0D, 64 vehicle speed = 100 km/h

PA 3, 2F, 80 fuel level = 50%

Use an OBD tester to confirm that the ECUsim automatically created and properly encoded PIDs $00 and $020: