Category: Vintage

And now a word from our sponsor …, you! Look elsewhere in this issue for an as yet untitled letters to the editor feature. We are now actively soliciting your letters and will reproduce in part some of the interesting ones. H you have a question or a problem, and we can’t find the answer in time to print it, we’ll throw it open to our readers for solution. Money talks. Unfortunately, we have a number of words on that…

By Bob Huelsdonk When inputting to a double loop by row, then jumping out to a double loop to total by column, it is necessary to revers the subscript order. This will not work in Applesoft BASIC because the right counters do not reset.  The following simple example will demonstrate: 80 PRINT  “INPUT ‘-1’ TO TERMINATE INPUTS” 100 FOR R = 1 TO 3 120 FOR C = 1 TO 3 140 INPUT A(R,C) 160 IF A(R,C) = – 1…

By Bob Huelsdonk Only line 30001 is required for less than 32K of Memory.  The first GOTO 30000 shows result with  greater than 32K of Memory. The second GOTO 30000 shows the result with less than 32K of memory. 30000 IF PEEK (203)>128 THEN 30002 30001 PRINT PEEK (202)+ PEEK (203)*256- PEEK (204)- PEEK (205 )*256;” BYTES FREE”: END 30002 PRINT 32767-( PEEK (204)+ PEEK (205)*256);” BYTES + “; PEEK (202)+( PEEK< (203)-128)*256 +1;” BYTES FREE”: END >GOTO 30000 30719…

By Mike Thyng In the previous articles, we’ve discussed types of files – sequential and random – and general facts and figures about the PERSCI floppy disk drive. This issue I’d like to explore some of the actual commands necessary to get data to and from the diskettes. Before you can write a file, you have to do something called “opening” it.  This defines to your program that some related data – let’s say names and addresses – is going…

A pencil, scratch pad and you – that’s all you need to convert HEX TO DECIMAL, or DECIMAL TO HEX. Based on the fact that unit, ten, hundred, and thousand columns have a unique set of values for hexadecimal, the above table will assist you convert either way. This remainder equals 8 in the LSB column, and. HEX(8). So, the HEX number for 14632 is,3928. This might seem cumbersome, but it is surprising how rapid this conversion can become with…

by Darrell Aldrich This is a brief description of the use of the color mask byte (Location 81210) for high re solution graphics in Apple Integer Basic. This mask specifies an 8 bit pattern of plottable X coordinates, with the pattern repeating itself every eight coordinates, going from left to right. The bits in this byte represent the colors violet and green, alternately. (See Figure 1). Suppose we want to mask off every other green bar on the screen as…

The following section covers use of the Apple II mini-assembler only. It is not a course in assembly language programming. The following section assumes the user has a working knowledge of 6502 programming and mnemonics. The Apple II mini-assembler is a programming aid aimed at reducing the amount of time requir.ed to convert a handwritten program to object code. The mini-assembler is basically a look-up table for opcodes. With it, you can type mnemonics with their absolute addresses, and the…

Documentation has been cited by Apple Computer as a cause of delay in shipping both the new ROM board and the Disk II. Discs have been rescheduled for shipping during the first week of July, while the Applesoft ROMs should follow within two or three weeks. Well worth waiting for!

Here is a patch to correct one of the few bugs found in Applesoft II. The HTAB function will space 2 places further to the right than intended unless corrected with this patch: POKE (HM-28), 202 where HM = the value of HIMEM: for your Apple. This should be done after loading & prior to running.

This handy little subroutine can be used in two manners; to fill a screen page with repetitive material or to determine the length of a screen page of print statements. Assume line 100 is a print statement with which you wish to fill the page. 100 PRINT” “:GOSUB 400 400 IF PEEK(37) < 18 THEN RETURN 410 POP:PRINT “FOR NEW PAGE HIT ANY KEY”:CALL 756:GOTO 000 Line 400 reads the cursor and finds whereitis on the page. If less than…

Don Williams will be our instructor again for two levels of Integer Basic Programming classes available to our members.   Beginning and Intermediate classes will be available, with the beginning class starting sometime in August. Details will be available in the next issue of Call-A.P.P.L.E.

If you have a newer Apple with the silent keyboard, Don Williams has written a short and sweet machine language routine to solve your problem. 0300:  48              PHA 0301 : A9 20        LDA #$20 0303: 8D 30 CO   STA $C030 0306: 20 A8 FC    JSR $FCA8 0309: 8D 30 CO   STA $C030 030C: 68              PLA 030D: 4C 1B FD   JMP $FDIB 0038: 00 03 Once you store the address ($0300) in location $38 and hit return, your keys will click…

Date: 20 June 1978 Time: 7:07 pm The meeting got off to a flying start at 7:07 PM as we introduced ourselves. Our official membership now stands at about 64, with 31 present at this meeting. (And in the two weeks since the meeting, has increased to over 100!) Val reported that the new Call -A. P. P. L. E. “Hot Line” has been installed and that the number is 932 -6588. (Where have we heard that number before?) This…

We are pleased to report the formation of an Apple user group south of the border, Apple Portland Program Library Exchange. We attended their organizational meeting in May and spent an enjoyable evening in Portland as the guest of Terry Ashton of Computerland of Portland, who also hosted the initial meeting. We are happy to see that their membership now numbers in the 30’s. Their dues and program rate structure approximate sours, and we anticipate a good deal of interaction…

By J.A. BACKMAN If you have dumped a program by hitting “RESET” when you meant to hit “RETURN” and Ctrl-C wouldn’t bring the program back – – I’ll bet the air was as blue around your APPLE II as it was around mine! – ! – ! A sweet little fix is a simple gadget that stops accidental keying “RESET” but does not stop its operation when it is needed. It does not hide the key, and doesn’t require lifting…

For all owners of the A.P.P.L.E. Library Pak 1A, please note: There is a partial dropout in program No. 8 (Color Game Pak) in early copies. Try loading at a higher volume setting. If this does not work, let us know and we will replace. The same issue occurs with our early copies of Basic Tutorial.

Last issue I talked about the general specs of the PERSCI 277 eight inch floppy disk drive. This issue I want to discuss some of the uses for a floppy disc and why anyone would even want one. But first, let me digress. Since Apple has announced its own Disc II, why should I be telling you about the Persci floppy? Two reasons. 1) Computer Components announced its own floppy as available before Apple did, and 2) I’m using one…

As usual, we are down to the wire again as it comes time to write this column. We are still receiving applications from all over the country as we pass the 110 mark in membership, and we would also at this time like to extend a special welcome to our first overseas member, Paul Moortgat who lives in Nieuwkerken, Belgium! There are many special features for new members in this issue, and we would like to refer you to the…

MEMORY RANGE* DESCRIPTION ———————– —————————————- 0.1FF Program work space; not available to user. 200.2FF Keyboard character buffer. 300.3FF Available to user for short machine language programs. 400.7FF Screen display area for text or color graphics. 800. 2FFF APPLESOFT BASIC compiler. (Cassette Tape Version) 800. XXX User Program (ROM version – A2B0009X installed) where XXX is maximum available RAM memory 2000.3FFF High Resolution Graphics Display page 1. May be used by Ror-1 (A2B0009X) version of App1esoft II only. 3000. XXX User…

By Bob Huelsdonk Some protocol is a must if you use a printer with greater than 40 columns with your Apple.  This comes about because it tries to write beyond the screen area and into the variables area in Integer BASIC or into the operating system in Applesoft.  The following fix will help prevent this problem: Start your printer driver routine with a JSR FC58.  This will home the cursor and clear the screen.  Do not return to the screen…