The Booster

by Phil Davies



Issue 15

May/Jun 85

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There are two versions of this program, one for the 400/ 800 and one for the XL models. The only difference is in the program to make the Cassette Booster. Once boosted a program can be loaded on any machine so you will have no problem if you upgrade to an XL

Fed up with waiting fifteen minutes for that program to load? Running short on cassette storage space? Look no further for Cassette Booster will not only save you valuable time but money as well.


The program will enable your own programs to be saved out to tape 50% faster than normal and programs thus saved are automatically loaded back in 50% faster. There is no special loader program or reprogramming required once Cassette Booster has been booted.


The cassette handling routine in ROM saves data out to tape at 600 baud (bits per second) but to take account of motor variations and tape stretch etc. it can load data at different speeds, usually between 300 and 900 baud.

The Cassette Booster inserts a new cassette handler into memory which writes data out at about 900 baud. This rate was chosen for two reasons. Firstly, rates in excess of 900 baud became unreliable with frequent loading errors and secondly, I wanted to avoid the need for a separate loader program having to be loaded prior to each program.

On loading, the computer calculates the baud rate from speed data automatically saved out with the program and adjusts itself accordingly to the faster rate.


The programs are in Basic and will run with any size memory. The BASIC program will create a machine code 'boot' tape. Type in the version specific to your machine and, having checked your typing with TYPO II, CSAVE a copy before running it. Now RUN the program. There will be an introductory message and a short wait before your computer 'beeps' twice. Place a blank cassette in the recorder then press Record and Play on the recorder and any key on the computer. The machine code data will be saved to tape.

When the recorder stops and the READY prompt appears on the screen make sure that you have CSAVEd the Basic program (just in case) and then rewind the machine code program you have just created. You are now ready to boot in the Cassette Booster.

If you wish to use the Booster to save your programs in future the following procedure should be followed each time you switch on your computer. Make sure that the Cassette Booster machine code program is in the recorder (NOT the Basic version). Switch on the computer with the START key held down. You will hear a single 'beep'. Press the Play key on the recorder and then any key on the computer. The Cassette Booster will automatically load into memory and protect itself from being erased by SYSTEM RESET etc. (only switching off the power will remove it) and will then hand over control to your BASIC or ASSEMBLER program.

You can now program away to your hearts content and when you CSAVE or SAVE or LIST to the cassette, your program will be automatically saved out faster and will henceforth load in faster every time. It's as easy as that!


The BASIC program POKEs the code for the boot maker into page 6 of memory and the code for the cassette handler into page 20. The USR call passes control to the boot maker which then takes the data for the handler from page 20 and saves it out to tape in boot format.

As page 20 is used for the data, this BASIC program will not work with DOS installed. If you want to save it to disk, save it before running it or the data will be corrupted.

The machine code Booster program cannot, unfortunately, be used with DOS installed either as both use the same memory area.

If you use English Software's ACE you can still enjoy the benefits of the Cassette Booster by developing your program with ACE installed as usual, saving the named program to tape, booting in the Cassette Booster, loading your program back in and then saving it out again at the faster speed. Interestingly, 100% machine code programs can also be 'boosted'. If you use one of the published back-up programs just install Cassette Booster first, then load and run the back-up program. This results in the back-up being saved faster, and as some of these programs normally take 10 to 15 minutes to load, the reduction to 5 to 10 minutes is a welcome benefit.

I hope that you find the program useful. All who have used it are now busily going through their program library and re-saving 'boosted' versions thus freeing more tape for additional programs. Now you have no excuse for not typing in all those long listings!

Booster for 400/800

AtariLister - requires Java

Booster for XL/XE

AtariLister - requires Java