The Microcontroller Idea Book - Jan Axelson's Lakeview Research

supply. The chip requires an additional inductor and capacitor, plus two resistors to set the
output voltage. Maxim’s data books have more details about this and similar chips.
Storing Programs on Disk
With BASIC-52’s ability to store programs in on-board memory, disk storage isn’t necessary.
But storing programs on the host system’s disk is convenient, since you can save as many
programs as you want without worrying about running out of program memory. Since the
programs are stored as ASCII text, you can write or edit them with any text editor, and then
upload them as needed to the target system.
Most communications software allows you to upload and download files. In Procomm Plus,
you use the PGUP and PGDN keys. In the Windows Terminal Accessory, use the Transfers
menu.
Uploading to the 8052-BASIC System
When you upload a program to the 8052-BASIC system, you have to ensure that BASIC-52
has enough time to process each line before the next one arrives. If there isn’t enough time,
you’ll have missing characters or lines in uploaded programs. There are a couple of ways
to ensure that your uploads are complete.
Most software allows you to add delays after each transmitted line or character. You can
experiment with different values to find the shortest delays that allow you to upload reliably.
If you keep your program lines short, the delays between lines can be shorter.
If these options aren’t available, try using a slower baud rate, which gives BASIC-52 a little
more time to process each line before the next one arrives.
Downloading to the Host Computer
Saving Programs
To download a BASIC-52 program from the target’s RAM to the host’s disk, type LIST
to list the current program, but before you press ENTER to execute the command, set up your
host’s software to download, or receive, an ASCII file. When prompted, specify a filename.
When the transfer is ready to go, press ENTER to send your program to the host. When you
see the READY prompt, end the transfer by whatever means your software requires. (In
Procomm Plus, press ESCAPE.) You should now have a file on disk containing the program
you just listed.
You can test your download by erasing the program in the 8052-BASIC system’s RAM, and
then uploading it back into RAM.
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