CANoodler is a simple CAN (not CAN-FD) interface, which provides logic-level 3.3V output. It's designed to be used with microcontrollers that have CAN blocks inside them, and in particular uses a pinout on some ChipWhisperer CW308 (UFO) Target boards.
As CANoodler is not isolated, be aware that you should be careful using this in a high-noise environment. The CAN-GND and I/O GND are connected directly together on this board. CANoodler is simple to use.
The solder jumpers specify which pinout you'd like on the male DB9 connector.
The default pinout is selected by shorting the LOWER and MIDDLE solder jumpers. It is used by many boards and the Peak CAN USB interface:
The "option" pinout is set by moving each of the three solder jumpers to short the UPPER and MIDDLE pads. This pinout is used by cheap ODB-II to DB9 connectors: