Control for DOT Matrix Printers Operating in Harsh Environment.
Abstract
A control processing method and apparatus for dot matrix printers which are subjected to relatively high levels of vibration and shock. Vibration and shock are detected and, in the event that a known safe vibration or shock level is exceeded, print line data being fed alternately to the print head from a pair of data print buffers coupled to the output of a logic data input buffer are inhibited while the input buffer temporarily stores the incoming data. Drive pulses applied to the stepper motor used to move the print head carriage are simultaneously stopped. When the detected level falls below a set threshold indicative of a safe operating level, normal operation is resumed with the print data again being fed from the input buffer to the print line buffers which are reactivated along with the carriage stepper motor. Additionally, any positional change of print head carriage during the existence of shock or vibration levels above the threshold value from the last valid driven position is determined and accordingly repositioned prior to continuing the printing operation upon cessation of the disturbance. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 06, 1985
- Accession Number
- ADD011846
Entities
People
- S. L. Everett Jr
Organizations
- United States Army