Rather an example of how NOT to do it.
We received a home-assembled ECU with a BT-serial (not RS232 but logiclevel serial "fbus") module inside ECU: an unsupported setup (connected wrong so it did not work and prevented wired VT communications; Disconnecting BT-RS232 => VT communication started to work immediately).
- Bluetooth inside a metal case will not work. (see "Faraday cage")
- v3 5V TXD signal => BT module expects 3V3 signal level, so might be damaged. 5V level TXD => 2k4 - (RX of BT module) - 4k7 - GND voltage divider is required to be safe.
- First serial port: when VT is connected PC TX => ECU RX cannot be driven by the BT module at the same time, so BT module must be disconnected for wired VT to work (in the usual setup this happens when DSUB9 connector is disconnected)
- but the module was connected inside the case to the ISP header, preventing the ST232 chip to drive main processor RX properly (preventing VT communications)
See BroadcastDatastreamAim for AIM only (not triggerframe), this way ECU => BT module one-way communication should work.
Second RS232 is preferred
- 2nd serial can also send AIM stream if configured so, and no VT problem. See BroadcastDatastreamAimSecondSerial
Possible Solutions:
- Should we provide a BT-RS232 module so that it can transmit from outside the metal case ? We also make a 2nd RS232 DSUB9/pin9=5V
- or... Should we connect 2nd serial TX => BT Module (inside the ECU) for AIM comm ?
- might work with ECU endplate removed
However we could not pair it with Android. The provided PW did NOT work for us (tried several Androids, and also tried 1234 1111 0000 PINs).
- Actually the module seems to be a HC-06, not a HC-05, although uncertain
- it does NOT respond to AT+PIN.... command, neither the AT+PSWD="1234" or AT+PSWD=1234 or AT+PSWD1234 AT+PIN=.... or AT+PIN="...." ...
- or AT+BAUD5 => no response (although configured 19200 baud already)
- AT+VERSION => no response
- AT+NAMEVEMS => OKsetname (this is the ONLY command it responds, weird).
We do not know how the module was used, although suspect that perhaps not with phone, but with another HC-06 module, or a PC.
Perhaps the module might have been partially damaged before, due to feeding strong 5V TXD signal to the 3V3 level RX input of the module.
- ignch2 and ch3 (only ign outputs with IGBTs in this 2 IGBT box) were reported "staying active", but actually operational.
- P259/ch6 = EC36/31 output was damaged, although apparently unused, and other p259 outputs were operational, we replaced p259 chip.
- VR/VR both primary and secondary trigger inputs were good.
- 4ch Active flyback was installed at home, without actual return to the onboard flyback trace (this is very wrong), although apparently nothing was damaged. Fixed (added the wire).
We are a bit puzzled, given that the reported outputs were good, and some other (apparently not actually used) output was faulty.
Mostly spent time with the non-standard, hack-installed HC-06 (or HC-05?) module (which partially responded to AT+... commands, mostly not), the purpose and actual setup of which is not clear (if talking to PC, or Android, or other HC-06/HC-05 module or other ?) .
A project page from MembersPage/Europe for that Porsche should be a good way to proceed. With outputs, any problems, and anything special (the specially installed BT-module, for example.)