GB1409544A - Control device for recording elements - Google Patents

Abstract

1409544 Control of printers COMPAGNIE HONEYWELL BULL 7 Sept 1972 [17 Sept 1971] 41642/72 Heading G4H A control device for the hammers of a chain printer comprising 10 sets of 16 hammers cooperating with 10 identical sets of 48 characters includes, for each hammer, a store R2 for the data to be printed, one of a series of shift registers R1 linked in such a way that they present to a comparator C in sequence the characters of the chain as they come into alignment with the hammer, and means responsive to an output from the comparator which indicates that a desired character can be printed at that position. A description is given with reference to Figs. 2, 3 (not shown) of how and when each character of each set comes into alignment with each hammer, and of how the registers R1 are to be interlinked (Fig. 4, not shown). The data to be printed is fed to and from R2 as an 8-bit parallel signal with a parity bit; the character availability data is shifted into and through the registers R1 corresponding to the hammers of a set, and is fed from the appropriate R1 to the corresponding C in the abovementioned format. Each "unit" (e.g. C4 for hammer 4) also includes enabling circuits (e.g. VF) for synchronizing the data flow through R1, R2 and C, parity checking circuits CP1, CP2, Fig. 7 (not shown) and a circuit (CO) which checks that a requested character is printed and that a character is only printed if it has been requested. It is stated that the control device may also find application in the fields of electro-optical and -acoustical recording and, in the case of temporary recording, in the fields of switching and addressing.