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@ -110,18 +110,21 @@ Pcap-ct does not work with Python 3.4. After update to Python 3.8, it works.
This chapter describes the start of a charging session, considering all layers.
Precondition: On charger side, there is a homeplugGP-capable device present, which is configured as CentralCoordinator.
1. The charger creates a "random" value for NID (network ID) and NMK (network membership key), and configures its homeplug modem with these values.
1. The charger (Supply entity communication controller, SECC) creates a "random" value for NID (network ID) and
NMK (network membership key), and configures its homeplug modem with these values.
1. The charger provides 12V on the control pilot (CP) line (State A).
1. The user connects the plug into the car.
2. The car pulls the 12V at CP line to 9V (State B).
3. The charger sees the level change on CP and applies 5% PWM on CP.
4. The car sees the 5%, and interprets it as request for digital communication. It wakes up its communication controller and homeplug modem.
4. The car sees the 5%, and interprets it as request for digital communication. It wakes up its communication controller (electric vehicle
communication controller, EVCC) and homeplug modem.
5. The car sees homeplug coordinator packets on the CP, and starts the SLAC sequence by sending SLAC_PARAM.REQ. Can be also two times.
6. The charger receives the SLAC_PARAM.REQ and confirms it with SLAC_PARAM.CNF.
7. The car sends START_ATTEN_CHAR.IND, to start the attenuation measurement. In total 3 times.
8. The car sends MNBC_SOUND.IND, to provide different sounds. In total 10 times.
8. The car sends MNBC_SOUND.IND, to provide different sounds (signals different frequency ranges). In total 10 times.
8. The homeplug modem in the charger should measure the signal strength, and report the values to the SECC in an ethernet frame ATTEN_PROFILE.IND.
However, the used homeplug adaptor seems not to support this feature. That's why we need to "guess" some attenuation values for the next step.
However, the used homeplug adaptor with AR7420 seems not to support this feature. That's why we need to "guess" some attenuation values
for the next step.
9. The charger sends ATTEN_CHAR.IND, which contains the number of sounds and for each group the attenuation in dB. Pitfall: The car may ignore
implausible values (e.g. all zero dB), and the process may be stuck.
10. The car receives the ATTEN_CHAR.IND. If it would receive multiple of them from different chargers (due to cross-coupling), the car
@ -130,8 +133,8 @@ decides based on the attenuation levels, which of the charges is the nearest.
12. The car sends SLAC_MATCH.REQ to the charger. This means, it wants to pair with it.
13. The charger responds with SLAC_MATCH.CNF. This contains the self-decided NID (network ID) and NMK (network membership key).
14. The car receives the SLAC_MATCH.CNF, takes the NID and NMK from this message, and configures its homeplug modem with this data.
15. Now, the homeplug modems of the car and of the charger have formed a "private" Homeplug network. The RF traffic can only be decoded by
participants who are using the same NID and NMK.
15. Now, the homeplug modems of the car and of the charger have formed a "private" Homeplug network (AV local network, AVLN). The RF
traffic can only be decoded by participants who are using the same NID and NMK.
16. The car wants to know the chargers IP address. In computer networks, a DHCP would be a usual way to do this. In the CCS world, a different
approach is used: SDP, which is the SECC discovery protocol. The DHCP may be also supported as fallback.
17. The car sends a broadcast message "Is here a charger in this network?". Technically, it is an IPv6.UDP.V2GTP.SDP message
@ -141,45 +144,47 @@ with 2 bytes payload, which defines the security level expected by the car. In u
this, it sends a "Neighbour solicitation". (This looks a little bit oversized, because only two participants are in the local network, and
their addresses have already been exchanged in the above steps. But ICMP is standard technology.)
20. The charger responds to the neighbor solicitation request with a neighbor advertisement. This contains the MAC address of the charger.
In the case, we use this pyPLC project as charger, we rely on the operating system that it covers the ICMP. On Win10, this works perfectly,
the only thing we must make sure, that the MAC and IPv6 of the ethernet port are correctly configured in the python script. Use
`ipconfig -all` on Windows, to find out the addresses.
21. Now, the car and the charger have a clear view about addressing (MAC, IPv6).
22. The car requests to open a TCP connection to chargerIP at port 15118.
In the case, we use this pyPLC project as charger (*EvseMode*), we rely on the operating system that it covers the ICMP. On Win10,
this works perfectly, the only thing we must make sure, that the MAC and IPv6 of the ethernet port are correctly configured in the
python script. Use `ipconfig -all` on Windows, to find out the addresses.
21. Now, the car and the charger have a clear view about addressing (MAC adresses, IPv6 addresses).
22. The car requests to open a TCP connection to charger at port 15118.
23. The charger, which was listening on port 15118, confirms the TCP channel. (Todo: not yet implemented)
24. Now, the car and the charger have a reliable, bidirectional TCP channel.
25. The car and the charger use the TCP channel, to exchange V2GTP messages, with EXI content.
26. The charger is the "server" for the EXI, it is just waiting for requests from the car. The car is the "client", it actively
initiates the EXI data exchange.
26. Todo: The car walks through different states to negotiate, start and supervise the charging process.
27. The car walks through different states to negotiate, start and supervise the charging process. From communication point of view,
the complete process uses XML data, which is packed in EXI frames, which in turn are transported in the TCP channel mentioned above.
28. Todo: Decribe the steps in detail.
## Change history / functional status
### 2022-10-19 Communication with Ioniq car established
### 2022-10-19 [*EvseMode*] Communication/AVLN with Ioniq car established
* Using a TPlink TL-PA4010P with firmware MAC-QCA7420-1.4.0.20-00-20171027-CS and the PIB configuration file patched for evse according to the open-plc-utils docu.
* Python software running on Win10, Python 3.10.8
* On control pilot, sending 5% PWM to initiate digital communication with the car
* Since the TPlink is configured as coordinator, it sends "alive" messages, and the IONIQ starts sending the SLAC_PARAM.REQ.
* Per keystroke, we trigger a SET_KEY before the car is connected. The TPlink responds with "rejected", but this is normal, the LEDs are turning off and on, key is accepted.
* Python script interprets the relevant incoming messages (SLAC_PARAM.REQ, MNBC_SOUND.IND, SLAC_MATCH.REQ) and reacts accordingly.
* After successfull SLAC sequence, all three LEDs on the TPlink are ON, means: Network is established.
* After successfull SLAC sequence, all three LEDs on the TPlink are ON, means: Network (AVLN) is established.
* In wireshark, we see that the car is sending UDP multicast messages to destination port 15118. This looks like a good sign, that it wants a ISO15118 compatible communication.
![image](https://user-images.githubusercontent.com/98478946/196766285-1c3152f7-31db-4b5f-98b1-9f1216f9b9de.png)
### 2022-10-19 Sniffing mode not yet working with the TPlink adaptors
### 2022-10-19 [*ListenMode*] Sniffing mode not yet working with the TPlink adaptors
* with a Devolo dLAN 200 AVplus, software INT6000-MAC-4-4-4405-00-4497-20101201-FINAL-B in original parametrization, it is possible
to see the complete SLAC traffic (both directions) which sniffing the communication between a real charger and a real car. This does
NOT work with the TPlink adaptors. They route only "their own" direction of the traffic to the ethernet. Means: The pev-configured device
does not see the real car, and the evse-configured device does not see the real charger. This is bad for sniffing.
### 2022-10-21 SLAC, SDP and ICMP are working
### 2022-10-21 [*EvseMode*] SLAC, SDP and ICMP are working
Using the TPlink and Win10 laptop as evse, the python script runs successfully the SLAC and SDP (SECC discovery protocol). Afterwards, the car uses
neighbor solicitation (ICMP) to confirm the IPv6 address, and the Win10 responds to it. The car tries to open the TCP on port 15118, this is failing
because of missing implementation of the listener on PC side.
### 2022-10-26 Network is established in sniffer mode
### 2022-10-26 [*ListenMode*] Network/AVLN is established
Using the TPlink in EVSE mode and Win10 laptop, listening to a communication setup between real car and real alpitronics, the python script
successfully extracts the NID and NMK from the SLAC_MATCH response, sets this information into the TPlink, and the TPlink turns three
LEDs on. Means: Network established. When we send a broadcast software version request, we get three responses: One from the TPlink, one from the
@ -189,7 +194,7 @@ is hidden, most likely because the TPlink "too intelligent", it knows who has wh
third participant in the network. Trace in results/2022-10-26_WP4_networkEstablishedButHiddenCommunication.pcapng
## Biggest Challenges
- [ListenMode] Find a way to enable the sniffer mode or monitor mode in the AR7420. Seems to be not included in the public qca/open-plc-utils.
- [*ListenMode*] Find a way to enable the sniffer mode or monitor mode in the AR7420. Seems to be not included in the public qca/open-plc-utils.
Without this mode, we see only the broadcase messages, not the TCP / UDP traffic between the EVSE and the PEV. Any idea how to enable full-transparency
of the QCA?
- [all modes] convert the EXI data to the readable xml (e.g. using https://github.com/FlUxIuS/V2Gdecoder, or https://github.com/Martin-P/OpenV2G).
@ -197,6 +202,7 @@ Evaluate different EXI decoders/encoders, regarding speed, correctness and stabi
- [all modes] replace the fix-configured addresses (MAC, IP) in the python script by the real one from the operating system
## Other open topics
- [EvseMode] Add listener to socket at port 15118
- [*EvseMode*] Add listener to socket at port 15118
- [*PevMode*] Testing
- improve docu (update layer diagram, improve hardware docu, add link to evse which provides the 5% PWM)
- (and much more)