GB1279902A - Improvements in or relating to control devices for controlling mechanical printers or perforators - Google Patents

Abstract

1279902 Printer or punch controller SIEMENS AG 25 Sept 1970 [26 Sept 1969] 45757/70 Heading G4H Device controlling a mechanical printer or punch for data carriers has a step-by-step and a fast speed feeding device. Data bytes from a processor DUA are converted at CU to 12 bit parallel code to be stored in a register REG. For each byte stored in the register a counter B2 is incremented. The bytes are e.g. to be punched on 80 column cards by setting up device EST enabled by clock pulses MT occurring one per column, the clock pulses also being fed to counter 52. When counters SZ, BZ are equal each byte is punched into its corresponding column and a circuit DU requests the next byte from the processor. If a series of zeros occurs which-do not involve punching operations they are detected by circuit LZE which causes circuit DU to request the next byte independently of clock pulses MT. Thus counter BZ can be incremented at a higher speed if a series of zeros are obtained. When counter B1 overflows a flipflop US is set to cause the printer or punch high speed feed to be operated. If the zeros are followed by a byte to be printed or punched this operation cannot occur until counters BZ and SZ are equal so that the byte is entered into its corresponding column.