By convention, buffers are preceded by a word count. The codice_31 (Define Constant) assembles a count word and the following codice_32 (Block Started by Symbol) reserves the required number of words for the buffer. The card buffer requires 80 words, one for each card column. Driver CARD0 reads each card column literally, using 12 of the 16 bits in the buffer word, with a bit set to on for each hole punched in the corresponding row for that column. The pattern of punches typically describes a text character using the Hollerith code. The console keyboard also gives input to the program in the Hollerith code, the only case of two devices using the same character encoding.