An ISOBUS-ready implement plugs into the tractor with one cable, shows its controls on the tractor's own screen and answers the tractor's joystick buttons. If your machine still ships with its own control box and cable, here is what the implement side needs to become ISOBUS-ready, where AEF conformance fits, and the three ways to get there.
The request usually comes through the dealers. Their customers already have an ISOBUS terminal in the cab and do not want a second box on the pillar.
What ISOBUS-ready means to the buyer
Neither ISO 11783 nor the AEF defines "ISOBUS-ready". Buyers judge it by four things in the cab:
- One plug. The implement's lead ends in the standard 9-pin ISO 11783-2 connector and goes into the tractor's rear external ISOBUS connector. Same socket on every tractor brand. No separate power feed.
- The machine on the tractor screen. The implement sends its screens to the tractor's Virtual Terminal (VT). The operator sees the machine's functions, settings and alarms on the terminal already fitted in the cab.
- Joystick buttons through AUX-N. The operator assigns implement functions to the tractor's joystick and armrest buttons from the tractor's own menu.
- Documentation and section control through Task Controller. Where the tractor runs a Task Controller, the implement logs work totals, works to prescription maps and switches sections by position.
On sprayers, spreaders and seed drills, the fourth decides the shortlist. The operator's view of the difference is in ISOBUS vs non-ISOBUS implements. This post is the manufacturer's side.
Four things the implement needs
1. An implement ECU on the CAN bus
The implement needs a control unit that joins the tractor's ISOBUS network as a node of its own, claims an address, reads your sensors and drives your valves. Its lead ends in the ISO 11783-2 connector, which carries CAN, power for the ECU and a separate power supply for the loads. Pin functions for both tractor sockets are in the ISOBUS connector pinout guide, and what the control unit itself does is covered in what an implement ECU is.
2. A Virtual Terminal object pool
The screens are not stored in the tractor. The ECU uploads them to the terminal when it connects, as an object pool: masks, soft keys, input fields, alarm messages. The operator judges your machine by it. The ISOBUS Virtual Terminal explained post goes through how the upload works.
3. AUX-N functions, if joystick control is wanted
The ECU publishes a list of auxiliary functions: boom fold, marker arm, fan on. The operator binds each one to a physical button on the tractor side. You decide which functions belong on a button. The AUX-N complete guide covers the assignment from the cab.
4. A Task Controller client, if documentation or section control is wanted
For TC-BAS (totals), TC-GEO (position-based work and prescription maps) or TC-SC (section control), the ECU sends the tractor's Task Controller a device description of the machine (geometry, sections, loggable values) and acts on what the TC tells it. The levels are explained in ISOBUS section control explained.
| What the implement needs | ISO 11783 part | Needed when |
|---|---|---|
| ECU and 9-pin connector | Part 2 (physical layer), Part 3 (data link), Part 5 (network management) | Always |
| Virtual Terminal object pool | Part 6 | Always, if the machine has an operator interface |
| AUX-N functions | Part 6 | The operator should control functions from the joystick |
| Task Controller client | Part 10 | The machine should document work, follow maps or switch sections |
AEF conformance is its own step
The AEF (Agricultural Industry Electronics Foundation) runs a conformance test for ISOBUS products. A machine is tested per functionality (UT, the AEF name for Virtual Terminal support, plus AUX-N, TC-BAS, TC-GEO, TC-SC and others), and passed functionalities are listed in the AEF database, where dealers and buyers check compatibility.
Software libraries can carry their own AEF certification. That means the protocol layer underneath has been tested. It does not certify your machine. The conformance test looks at the finished product: your object pool, your AUX-N functions, your device description, running on your ECU. It comes after the software works, and you plan and budget for it separately.
Passing the test is not the same as working on every tractor. Terminals from different brands behave differently on ISOBUS, and the only way to know is to plug in.
Three routes to an ISOBUS-ready implement
Build in-house on a software stack
Your team picks an ISOBUS software stack, designs or buys the ECU hardware, writes the object pool and the control logic, and runs the tests. You own everything. You also carry the embedded development, the EMC testing of your hardware, access to tractors to test against, and the staff to maintain it all while the machine is built. This suits a manufacturer with an electronics team and enough ISOBUS models to keep it busy.
Buy a configurable controller and program it yourself
A generic ISOBUS controller or gateway arrives with the bus communication running. Your engineers set up the I/O and build the screens with the vendor's software. It is faster to start than a full stack. You still need someone who understands ISOBUS, the tractor testing is still yours, and the screens are limited to what the vendor's software allows. Check which approvals the controller carries before you assume the EMC work is done.
Commission a turnkey project
A partner develops the ECU software and the screens for your machine, tests them and maintains them. You supply the machine knowledge. This is what ETERVO Oy, the company behind ISOBUS Block, offers to implement manufacturers.
ETERVO develops and maintains the software, the Virtual Terminal interface and the integration with your machine. The scope is Virtual Terminal, AUX-N and Task Controller, built on AEF certified ISOBUS software libraries. AEF certification of the finished machine is a separate step. The control unit is designed, tested and built in Finland, sits in a sealed IP69 aluminium housing, and carries CE, E17 automotive EMC and RoHS 2 approvals, so its EMC testing is already done. It is delivered with flying leads that you wire to your machine's own sensors and valves, with the I/O defined per project.
The operator interface carries your brand, and the screens and control logic are designed around your machine. Before delivery, the software runs on a test bench with the same sensors and valves as your machine, wired the same way, and then on real tractors. Support runs for as long as the machine is in production. Ownership and licensing are agreed per project. What such a project contains, step by step, is in what an OEM ISOBUS project contains.
The three routes compared
| In-house on a software stack | Configurable controller, programmed by you | Turnkey project (ETERVO) | |
|---|---|---|---|
| Who writes the screens | Your team | Your team, within the vendor's software | The partner, designed around your machine |
| Who tests on tractors | You, on the tractors and terminals you can get access to | You | The partner, on a test bench wired like your machine and on real tractors |
| Updates during the production life | Your team, for as long as you build the machine | Your team, plus the vendor's updates to the controller | The partner, for as long as the machine is in production |
| EMC approvals on the control unit | Yours to test | Depends on the controller you buy | CE, E17 and RoHS 2 on the control unit, EMC testing done |
| AEF certification of the finished machine | Separate step | Separate step | Separate step |
The last row is the same on every route. So is the machine's own CE marking, which stays with you as the manufacturer.
What to prepare before you talk to anyone
Whichever route you pick, bring these to the first meeting:
- Every sensor and valve on the machine. Type, signal, and whether each valve is on/off or proportional.
- The functions the operator needs. What your control box does today, what belongs on the screen, what belongs on a joystick button.
- The tractor brands your dealers sell. This decides which terminals the machine gets tested on first.
- Whether you need Task Controller, and at which level. TC-BAS, TC-GEO and TC-SC each add work. Know which ones your buyers ask for.
- Your production plan. How long the machine stays in production, and how field updates should work.
Frequently Asked Questions
What does ISOBUS-ready mean for an implement?
The implement connects with the standard 9-pin ISOBUS connector, shows its controls on the tractor's Virtual Terminal, and takes commands from the tractor's buttons through AUX-N. Task Controller support is often part of it, not always. The term has no official definition, so buyers check the AEF database.
What is an ISOBUS ECU?
It is the implement's own control unit on the ISOBUS network. It reads the machine's sensors, drives its valves, uploads the screens to the tractor terminal, and exchanges messages with the tractor over CAN.
What does ISOBUS programming involve?
The ECU software that runs the machine and talks ISO 11783, the Virtual Terminal object pool for the screens, and where needed the AUX-N functions and the Task Controller device description. Then testing on real tractors, because terminals from different brands behave differently.
Is an implement AEF certified if its software libraries are?
No. Certified libraries mean the protocol layer has been tested. The finished machine goes through the AEF conformance test as its own step, with its own screens, functions and device description.
Can an owner make an existing machine ISOBUS-ready without the manufacturer?
Only the switching side. An owner who wants to add switched outputs to a machine, such as work lights or solenoid valves, can fit a relay module like ISOBUS Block and control them from the tractor screen and joystick. Screens for the machine's own functions, Task Controller and section control need an implement ECU built for that machine.
Building an implement and being asked for ISOBUS? Talk to ETERVO Oy about ISOBUS control for your machine: ECU software, Virtual Terminal screens, AUX-N and Task Controller, supported for as long as the machine is in production.