CANchecked MCE18 - Can Bus Expansion

MCE18 stands for "Multifunction Can Bus Extension" with 18 connections - why is this module needed? Our displays have four analogue inputs. However, for some applications this may not be enough and you need more inputs.

It makes sense to map this using the flexible Can Bus protocol. For this purpose, the sensors are connected to our MCE18 and sent via CAN bus to the device to be received - e.g. one of our displays.

But even freely programmable control units only have a limited number of inputs. This can be easily expanded with our module and sent directly to the control unit. 

Features:
9 analog inputs (0-5V)
6 digital inputs (on/off)
3 digital outputs (on/off LOW SIDE 0.5A) (new in v2!)

Tested with:

- CANchecked MFD28/MFD32/MFD32S
- MaxxECU
- Ecumaster
- LinkECU
- Haltech (emulates an IO Extender A+B or just B)
- Syvecs (coming soon)
- Motec (coming soon)
- AIM

This device is also available without a housing:  CFE18 – can switch board

– hardware –

Scope of delivery:

• MCE18 with housing
• Connector Superseal 34pin (TE 4-1437290-0)
• Pins Superseal 1.0 20AWG (TE 3-1447221-4)
• 3 jumpers

– pin assignment –

– jumper configuration –

If you remove the front 4 screws, you can pull off the housing. There are three jumpers on the back.

1) JP1 inserted activates the 120 ohm resistor for the Can Bus
2) JP2 inserted activates the 1K1 pullup resistor for A1 and A2
3) JP3 inserted activates the 1K1 pullup resistor for A6 and A7

By default, all jumpers are removed

– Default CAN Bus Stream –

The input data is queried and transmitted every 50ms (20Hz – changeable). The data is transmitted as "unsigned big endian".

As soon as 12V and ground are connected, the green status LED on the back lights up.
Can Bus ID: 0x700 ( Base Data CAN ID – changeable)

MCE18 TRI File Download MCE18/CFE18 Tri File
MCE18 DBC File Download MCE18/CFE18 DBC File

The configuration or modification of the Can Stream is described in CFE18 - Can Bus Function Extension .

– AIN smoothing –

If the analog inputs fluctuate too much, they can be smoothed out using software. This can be configured separately for each analog input.

The higher the smoothing, the calmer (smoother) the value becomes, but it also reacts more slowly to fluctuations. You have to find a healthy middle ground here.

Values ​​go from 1-250 - the higher the more smoothing, 1= no smoothing.

The setting is made via Can Bus - see CFE18 => " Configuration options "

– Control unit / ECU configuration –

The analog inputs provide a 10-bit resolution and therefore values ​​from 0 to 1023. The value must be converted in the control unit. All values ​​are "unsigned big endian"

Examples:
5V voltage AIN0
0x700 Byte0+1
Multiplier: 5; divisor: 1023; Offset: 0

or multiplier: 0.004887585533

Exhaust gas temperature (type k) AIN7:
0x702 Byte6+7
Multiplier: 1250; divisor: 1023; Offset: 0

or multiplier: 1.2218963832

Either the individual bytes are used for the digital inputs. Eg DIN6: 0x702 byte 6 or the bit mask at 0x702 byte2

eg DIN6: 0x702 Byte2 Mask:0x40

Here is a little cheat sheet to do the calculations for a MaxxECU: maxxecu-sensor-calculation.xlsx

– Documentation / Download –

MCE18 TRI File Download MCE18/CFE18 Tri File
MCE18 DBC File Download MCE18/CFE18 DBC File