Performance Enhancements for the IBM 5201 Quietwriter Printers
Original Publication Date: 1988-Nov-01
Included in the Prior Art Database: 2005-Feb-15
A method is described which improves printing performance on the IBM 5201 Quietwriter printers. The original microcode in the IBM 5201 Quietwriter printer was supposed to move the printhead in an uninterrupted, or slew, mode for each Forward Relative Movement (FRM) control with a value of 4 to 20 printer units (120ths of an inch). Instead, the printer moved the printhead in an interrupted, or tab, mode. This tab mode greatly reduced printing performance. This problem was eliminated by producing new microcode that allows the printer to remain in slew mode for each FRM control of even value between 4 and 48 120ths of an inch. Therefore, for the IBM 5201 and IBM 5201-2 Quietwriter printers, DisplayWrite 4* (DW4) always sends an FRM control of even value when moving forward a horizontal distance of 4 to 48 120ths of an inch.