Closed clfregis closed 5 years ago
Hello guys, again another amateur mistake. All connections described above are correct. However, the Vin pin of ESP32 does not provide 5V. It is slightly less than that (4.75V, even less when loaded). I thought it was ok, because we always have a margin of operation on those chips and dismissed the possibility of an error due to the value of this voltage. Then, after trying hundreds of different approaches to solve the problem, I decided to take a look on MCP2551 datasheet, then I found that the minimum value of the VDD for this particular chip is 4.5V (so we do not have a good margin of operation here). Thus I decided to use an external 5V power supply. On top of that, since the emulator is near the receptor (aka short line) I plugged a ballast resistor of 120 Ohms between CANH and CANL (on some modules there is a jumper to this). Now is working like a charm.
Hi guys!! I've followed your instructions to deploy the program at ESP32 microcontroller. Everything worked fine, I was able to connect to it using my phone and also was able to track the log of TX using terminal. However, I was not able to read the transmitted data using a CAN Module MCP2515 Module with arduino UNO. The receiver end is working fine as well, since I tested it in a car using the code at the end of this post (some comments are in portuguese, sorry for that) and was able to get RPM data. Thus, I think that maybe the problem is in the connection that I did, which is the following: Instead of using the WROOM32 alone I used the ESP32 DEVKIT V1. Also, I was not able to find SN65HVD230, so I used MCP2551 Module. The voltage supply of this module is 5V, so it was necessary to interface the communication using this logic level converter. So, the connections are as follows:
D4 (GPIO4 from ESP32 module) -> LV4 (logic level converter) D5 (GPIO5 from ESP32 module) -> LV3 (logic level converter)
HV4 (logic level converter) -> CRX (MCP2551 Module) HV3 (logic level converter) -> CTX (MCP2551 Module)
CANH (MCP2551 Module) -> CANH (MCP2515 Module) CANL (MCP2551 Module) -> CANL (MCP2515 Module)
POWER SUPPLY: -Logic Level Converter
VIN (ESP32 Module) -> HV (Logic Level Converter) GND (ESP32 Module) -> Both GND (Logic Level Converter) 3V3 (ESP32 Module) -> LV (Logic Level Converter)
-MCP2551 Module
VIN (ESP32 Module) -> VCC (MCP2551 Module) GND (ESP32 Module) -> GND (MCP2551 Module)
Am I missing something? I do not have oscilloscope here to see if the data is arriving at the logic converter or at the MCP2551 module. Do you have any suggestion? I thing that maybe the VIN voltage (which comes directly from USB VDD) is not sufficient to run the MCP2551.
P.S.: I've checked dozen times the above connections using a multimeter (continuity test) to avoid any faulty wiring.
P.P.S.: I've maintained the default values in menuconfig (pins, etc). I only needed to change the flash memory to a higher value.