HP-42s double speed modification and printing

[Bernd Grubert]

(11-06-2020 01:15 AM)Valentin Albillo Wrote:  "Since the HP-42S is capable of sending information faster than it can be printed by the HP 82240A infrared printer, the calculator uses a delay time to avoid losing information."

You're right. The mechanics of the printer are the bottle neck. But with the Redeye-Interface project from Martin and Meindert it should really print at double speed. But actually that was was not my reason for the modification. I just wanted to increase the calculation speed.

In the meanwhile I exchanged the crystal. Unfortunately the printer doesn't work at all . I'm afraid the timing is too fast now. Same holds for the RedEye Interface. Here it might be possible to adapt the software of the Arduino board to the faster timing.

Regards
Bernd