In a method for causing data to be written to a non-volatile medium, an indication of a size of a sector or a sector fragment may be transmitted to a channel device, and an indication of a size of a codeword to be written in the sector may be transmitted to the channel device. Data to be iteratively encoded and written in the sector as the codeword may be transmitted to the channel device. A write gate signal corresponding to the sector or the sector fragment may be transmitted to the channel device to indicate to the channel device when to write to the sector or the sector fragment.