#Canbus to arduino nano pinout install#

#Canbus to arduino nano pinout install#

If you plan to use I2C on this board, install a 328p right from the start, and save yourself a lot of headaches!

A word of action though, I had strange issues with I2C on the Atmega8a with Mini core, to such an extent that I2C does not work at all? The 8a/88 or 168 are less well known, have much less memory and flash area, and will thus be cheaper. I believe this is an advantage, especially with the current chip prices, where my last quote for an ATMEGA328P-AU was 69$USD!!!! This is in comparison to the 4 to 5 USD each for an ATMEGA8a or ATMEGA168 ( We must also remember though that the 328p is very well known, and thus have higher demand. The CAN Relay Module can use any of the ATMEGA8a/88/168/328 AVR microcontrollers, as the pinout is identical. Please note that in this case,Ģ) The LDO regulator will not be in operation. You could also power the module with REGULATED 5v DC, directly from any 5v header pin. Not paying attention to this will result in damage to the MH-CD42 Module. When the MH-CD42 module is in use, the total DC input voltage through the DC input adapter SHOULD NOT exceed 5.5v DC! This is a limitation in the operating parameters of the MH-CD42 module. If you place the H2 Jumper in the VBAT position, you need to install the MH-CD42 module to provide power to the rest of the PCB, as well as keep the LiPo battery or 18650 Cell charged… This will divert the DC Voltage(Up to 12v) from the DC input adapter to the build-in 5v LDO voltage regulator to power the device. The MH-CD42 Module, and LiPo or 18650 Battery are completely optional, The device can function without these, by moving the H2 jumper to the VREG position as already mentioned above. Firmware can be uploaded with an AVRASp, USBASP, Arduino as ISP or even an external USB-to-Serial converter ( providing that you load a bootloader into the Atmega Chip).Īll of the unused GPIO pins on the ATMEGA chip is broken out into headers, with the exception of D10 ( which is used as CE/SS on the MCP2515 CAN controller), D9 which is connected to the Interrupt from the MCP2515, and D4, which is used to control the onboard Relay. As space was at a premium, and to ensure that there are the absolute minimum additional components that will consume power when operating from the battery, I have not included any USB-to-Serial converters onboard. The CAN Relay Module PCB was designed to be as compact as possible, with a total footprint of the standard Arduino UNO. This feature makes it ideal for my intended use, as I would only be needing battery power at night when the off-grid solar powered inverter is not actively charging the main batteries, and providing 220v AC. The Module can also be powered directly from up to 12v DC by placing Jumper H2 in the V-REG position…Īs mentioned in a previous project, the MH-CD42 module can provide up to 2A of current to charge a battery and provide 5V DC on a direct bypass circuit to power the rest of the circuit while the battery is being charged.

Today, I will focus on the design of the node device, an Arduino compatible CAN Relay Module PCB, with a built-in, CAN Controller and Transceiver ( MCP2515 and TJA1050 ), and the option to be powered from a LiPo battery (18650 or Single 3.7v Lipo cell), with charging provided by an MH-CD42 Module, similar to that used in the SX128x project mentioned above. In a previous project, I introduced the LoRa-CAN Gateway, which will be used to send/receive messages from the master control unit, the SX127x-RA-02-Module. It was logical to decide to use CAN-BUS for communication between my LoRa-CAN Module and remote nodes in my ongoing farm telemetry system. CAN-Bus allows us to add a lot of devices to a single bus (theoretically up to 127, with a practical limit of about 110).