A towed agricultural machine for tillage purposes andor for sowing seeds is disclosed. A method includes initiating a write operation to write first data to a first word line of a multi-level cell block of the non-volatile memory. A spring applies a downward spring force on the parallel linkage to apply a downward force on the packer wheel so that the spring force increases as the parallel arms pivot upwardly and decreases as the parallel arms pivot downwardly.