Tape Header Reader waits for you to start a tape and reads the next header block. For a BASIC program it shows the name, the program and variables lengths and the auto-start line; for code it shows the load address and length; arrays are named as numeric or character arrays. If the block it read was not a header it says so, and you can read another.
The program has no author’s name. It was on several of Bob Swoger’s disks.
Program Analysis
A 44-byte routine POKEd from DATA at 29000 switches in the TS2068’s extension ROM through ports 255 and 244, calls its tape-loading routine at 00FCh to read 17 bytes into a buffer at 29044, and switches the home ROM back. BASIC then decodes the buffer with DEF FN f(x)=PEEK x+256*PEEK (x+1).
Notable Techniques
- The type byte is preset to 4 before reading, so a block that was not a header is recognised when it is still 4 afterwards.
- The name is printed over a row of underscores with
OVER 1.
This copy came from a Larken disk; only its disk save and menu lines were removed. Tested in ZEsarUX on a stock TS2068, reading BASIC and code headers.
Image Gallery
Source Code
10 POKE 23658,0: BORDER 1: PAPER 1: INK 9: CLS
20 CLEAR 28999
30 LET s=29000
40 LET d=s+44
50 DEF FN f(x)=PEEK x+256*PEEK (x+1)
60 LET dh=INT (d/256)
70 LET dl=d-256*dh
80 DATA 175,55,221,33,116,113,17,17,0,243
82 DATA 245,219,255,203,255,211,255,219,244,50
84 DATA 115,113,62,1,211,244,241,205,252,0
86 DATA 58,115,113,211,244,219,255,203,191,211
88 DATA 255,251,201,0
90 FOR n=0 TO 43: READ c: POKE s+n,c: NEXT n
100 CLS
110 POKE d,4
120 PRINT AT 10,8;"START THE TAPE-"
130 RANDOMIZE USR s
140 CLS
150 LET type=PEEK d: IF type=4 THEN GO TO 400
160 LET a$=""
170 FOR n=1 TO 10
180 LET a$=a$+CHR$ PEEK (d+n)
190 NEXT n
200 PRINT "Name: __________"; OVER 1;AT 0,6;a$''
210 LET len=FN f(d+11): LET start=FN f(d+13): LET pa=FN f(d+15)
220 LET va=len-pa
230 IF type THEN GO SUB 300: GO TO 410
240 PRINT "Program type: BASIC."''
250 PRINT "Program area: ";pa;"bytes."''
260 PRINT "Variables area: ";va;" bytes."''
270 IF start>9999 THEN PRINT "No auto-start.": GO TO 410
280 PRINT "Auto-start at line ";start;"."
290 GO TO 410
300 LET t$="Code Block."
310 IF type=1 THEN LET t$="Numerical Array."
320 IF type=2 THEN LET t$="Character Array."
330 PRINT "Program type: ";t$''
340 IF type=3 THEN PRINT "Destination Address: ";start;"."''
350 PRINT "Length: ";len;" bytes."
360 RETURN
400 PRINT FLASH 1;AT 10,6;"THIS WAS NO HEADER!"
410 PRINT AT 20,1;"Do you want another go (y/n)? "
420 PAUSE 0: IF INKEY$="y" THEN GO TO 100
430 STOP
9992 SAVE "HEADER.B1" LINE 10
9998 CLEAR 6e4Note: Type-in program listings on this website use ZMAKEBAS notation for graphics characters.