US Patent 11975547 Fluid ejection controllers to pivotally hold firing boards

In one example in accordance with the present disclosure, a fluid ejection controller is described. The fluid ejection controller includes a firing board to pass control signals to a fluid ejection device to eject fluid from the fluid ejection device. A mount pivotally holds the firing board between a disengaged position where electrical pins of the firing board are not in contact with electrical pads of the fluid ejection device and an engaged position where the electrical pins are in contact with the electrical pads. The mount includes a slot to receive the fluid ejection device and at least one biasing spring to bias the firing board away from the fluid ejection device during insertion of the fluid ejection device. The fluid ejection controller also includes a handle coupled to a cam shaft to move the firing board between the disengaged position and the engaged position.