Lpvideo

David E. Powers 10 Wilben Ct.

New Hyde Park, NY 11040

Often I want hard copy of everything on my TRS-80 video screen. A favorite method to print out the TRS-80 display is to POKE the printer driver address into the video control block in dedicated RAM (POKE 16414, 141: POKE 16415, 5). Thereafter every PRINT command will act as an LPRINT.

The trick is clever but very limiting. While it is in place, the CRT is inactive, the keyboard is tied to the line printer (you won't see what you are typing until you press ENTER) and output required on the screen will be sent only to the printer. The POKE routine and the one to cancel it (POKE 16414,88: POKE 16415, 4) are second-best techniques.

What's LPVIDEO

LPVIDEO (line print video), presented here in two versions, is a generalized subroutine to produce hard copy of everything on the TRS-80 screen, without interrupting the video display or compromising readability of keyboard input. Both versions produce identical machine language software which may be

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TOW TO PRINT M CONTENTS OF T)C VIDEO SCREEN TO T>€ LltCPRIKTfR

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