To: John McCluskey@JPL-VLSI.ARPA c/o INFO-IBMPC@USC-ISIB
From: R. J. Lehman
Subject: Hercules Graphic Card Screendump
(Note: I'm following crude instructions on how to get a message into
INFO-IBMPC. Please pass this along as appropriate. Thanks.)
1. Hercules sells a package, GRAPH-X (about $50.), which includes the
PCDOS utility, HARDCOPY.COM, to do screendumps.
2. Since the HARDCOPY screendump is quite small, I wrote the BASIC
program, SCRNDUMP.BAS (appended to this text), which produces a 7 X 10
inch picture on an Epson FX-type printer. The annotation in the program
should help your friend figure out how to get a graphics dump. Running
under BASICA, the program is S-L-O-W, but it moves along at the printer's
speed when compiled. I hope this helps.
R. J. Lehman
University of Michigan
Transportation Research Institute
2901 Baxter Road
Ann Arbor, MI 48109
(Program follows...)
1 ' Program: SCRNDUMP
2 ' Purpose: Produce full page hard copies of Hercules screen-image files.
3 ' Author: Richard Jeff Lehman 407 UMTRI/2901 Baxter Rd. Ann Arbor, MI 48109
4 ' Last revised: 1/5/84
5 ' Notice: Copyright (C) 1984, R. J. Lehman. All Rights Reserved.
6 ' Notice: Permission is hereby given for non-commercial duplication, modification and distribution.
7 '
8 '
10 CLS:KEY OFF:DEFINT A-O:DEFSTR P-U:DIM BS(86,3)
11 '
12 ' Array BS is used to hold the starting address of each of the 348 rows
13 ' which comprise a Hercules screen.
14 '
15 ' The following line computes the initial values.
16 '
17 FOR I=86 TO 0 STEP -1:FOR J=3 TO 0 STEP -1:BS(I,J)=J*8192+I*90:NEXT J,I
20 DEF SEG=&HB000:' Address of Hercules screen 0
25 WIDTH "lpt1:",255:' Prepare printer
30 INPUT"Enter name of screen image file to print: ";FILENAME$
35 ON ERROR GOTO 1000:' Don't crash if file not found, etc.
40 BLOAD FILENAME$,0:' Load image into Hercules' memory.
42 ON ERROR GOTO 0:
45 FOR I=1 TO 3:LPRINT" ":NEXT:' position paper so image will be centered
60 SETUP=CHR$(27)+"3"+CHR$(24)+CHR$(27)+"*"+CHR$(6)+CHR$(184)+CHR$(2):' Epson command line. Says "space 9 lines/in, and use CRT graphics II print type {90 dots/in}, with (184+2*256 = 696 = 2*348) dots/line."
70 FOR K=0 TO 89:' Only 90 steps across the screen because the stuff will be printed in byte-sized chunks. (90*8=720 columns on the Hercules screen)
75 LPRINT SETUP;:' Tell the printer again, every line.
80 FOR I=86 TO 0 STEP -1:FOR J=3 TO 0 STEP -1:' Print four rows at a time, from bottom to top
90 A=BS(I,J)+K:T=CHR$(PEEK(A)):IF T<>CHR$(13) THEN LPRINT T;T; ELSE LPRINT CHR$(15);CHR$(15);:' Get the contents of screen memory byte, treat it like a character.
92 ' If the character is <CR> (CHR$(13)), fudge it and print something that will look OK, because the IBMPC burps an extra <LF> (CHR$(10)) when printing a <CR>, and that can louse up a perfectly decent looking picture,
93 ' because the Epson can't tell a <LF> meant as line feed from one meant as data when it's printing a picture. (It took me quite a while to figure this out.)
95 NEXT J,I:LPRINT:NEXT K:' End of loops, print WITH <CR> to end the line.
100 LPRINT CHR$(27);"2";:' Put Epson back in standard text mode.
110 FOR I=1 TO 3:LPRINT" ":NEXT:' Go to top of next page.
120 CLS:PRINT:INPUT"Print another file? ";SN:SN=LEFT$(SN,1):IF SN="y" OR SN="Y" THEN 30:' Do it all again, if desired.
130 END:' Or not. As you wish.
1000 CLS:PRINT"I/O Error #:";ERR;". Try again":RESUME 30:' Disk error message
