Contents
Introduction
Chapter 1
 SETTING UP THE ACE
Chapter 2
 TYPING AT THE KEYBOARD
Chapter 3
 LOADING PROGRAMS FROM TAPE
Chapter 4
 DEFINING NEW WORDS
Chapter 5
 SIMPLE ARITHMETIC
Chapter 6
 DEFINING NEW ARITHMETIC WORDS
Chapter 7
 ALTERING WORD DEFINITIONS
Chapter 8
 WORDS THAT ARE REALLY NUMBERS
Chapter 9
 MAKING DECISIONS
Chapter 10
 REPEATING
Chapter 11
 SOUND
Chapter 12
 THE CHARACTER SET
Chapter 13
 PLOTTING GRAPHS
Chapter 14
 SAVING PROGRAMS ON TAPE
Chapter 15
 FRACTIONS AND DECIMAL POINTS
Chapter 16
 READING THE KEYBOARD
Chapter 17
 OTHER WAYS OF COUNTING
Chapter 18
 BOOLEAN OPERATIONS
Chapter 19
 MORE ADVANCED ARITHMETIC
Chapter 20
 INSIDE THE DICTIONARY
Chapter 21
 STRINGS AND ARRAYS
Chapter 22
 VOCABULARIES
Chapter 23
 INSIDE COLON DEFINITIONS
Chapter 24
 HOW THE MEMORY IS LAID OUT
Chapter 25
 MACHINE CODE
Chapter 26
 EXTENDING THE ACE
Appendix A
 QUICK GUIDE FOR 'FORTH' ENTHUSIASTS
Appendix B
 ERRORS
Appendix C
 THE JUPITER ACE - FOR REFERENCE
Appendix D
 QUICK GUIDE FOR 'FORTH' ENTHUSIASTS
INDEX

Chapter 3

LOADING PROGRAMS FROM TAPE

If you already have some cassette tapes with Ace programs recorded on them then this chapter tells you how to load those programs into the computer; otherwise skip the chapter for the time being. You can only use programs that have been recorded specifically for the Ace, and not for some other computer.
 You will need an ordinary cassette tape recorder - preferably a cheap one, because expensive hi-fi stereo machines often do things to the signal that the computer won't understand. It needs to have a socket for a microphone and a socket to run an earphone, and these two sockets should fit the plugs on the pair of leads supplied with the computer.
 Now connect the computer to the tape recorder with this pair of leads. One of them connects the earphone socket on the tape recorder to the socket marked EAR on the computer (make sure it's the same lead at both ends - you can tell by the colours of the plugs). The other, although you won't actually need it yet, connects the microphone socket on the tape recorder to the socket marked MIC on the computer:

A tape can have several programs, coded by the computer into a signal suitable for recording on tape. Each program has a name of up to ten characters, again coded electronically onto the tape. Let us suppose that your tape has an interesting program called DVLC - it runs a game in which you are menaced by hundreds of vehicle licence application forms falling out of the sky, and you have to catch them and destroy the enclosed vehicle registration documents.

 Put your tape in the tape recorder, and wind it to somewhere before the program DVLC - or right back to the beginning if you're not sure where it is. Turn the tone control, if there is one, to minimum (i.e. most bass, least treble), and turn the volume control to three quarters maximum. Type in

LOAD DVLC

press ENTER, and start the tape playing. (Note — normally on the Ace it doesn't matter whether you use capital letters or lower case; but for the name of a program on tape you must get it exactly right.)
 As the computer finds various programs on the tape, it will write their names on the television screen. Eventually it will write

and, after a few quiet clicks, OK. The program is now successfully loaded, and you can stop the tape. What the program consists of is the definitions of some more FORTH words, additional to those built into the computer. The instructions for the program should tell you how to use these words.

If the loading failed for any reason Of it just goes on and on, you can stop it by pressing SPACE - it will say 'ERROR 3'), then

● Check that the computer is correctly connected to the tape recorder.

● Check that you typed the name of the program correctly, distinguishing between capitals and lower case.

● Check that the plugs fit properly in the sockets on the tape recorder. On some tape recorders the plugs may need to be pulled out just a fraction of an inch from being fully in.

● It is possible that the volume setting matters a lot with your tape recorder. Try two or three different settings, including maximum.

● It may help to clean the tape heads on the tape recorder.

If you're not sure what programs are on the tape, rewind it to the beginning, type

press ENTER and start the tape. The computer will eventually write up the names of all the programs.
 You can have more than one program in the computer at a time (if there's room). Just load them one after another.
 Some parts of programs may need to be loaded differently, with a word BLOAD. The instructions for the tape should tell you about this. The most usual form is

where 'name' means whatever name is used on the tape (like DVLC).