The Microcontroller Idea Book - Jan Axelson's Lakeview Research

Successful assembly is a good sign, but it doesn’t mean that the program is error-free. As in
any programming language, a line of code may contain instructions that are valid, but that
do not do what you intended. It’s a good idea to at least scan the listing created by the
assembler before you try to run a routine, to look for obvious errors.
Different assemblers may have slightly different syntax rules. For example, some require
org and end to have a leading period (.org, .end). Check your assembler’s documentation
for the specifics.
Uploading a Program
Calling Assembly-language Routines
When you’re ready to load the program into RAM, boot your 8052-BASIC system, connect
the serial link to your personal computer, and run your communications software. Use the
software to upload Listing B-1 or B-2, in the same way that you upload any BASIC-52
program from disk.
For loading Intel hex files, you can set up your host computer’s software so that it waits to
receive the BASIC-52 “>” prompt (ASCII code 62) after each uploaded line. This will ensure
that BASIC-52 has enough time to process each line before the next one arrives. Use this
method only with Intel Hex files, not BASIC-52 programs. If a BASIC-52 program contains
any “>” (greater than) operators, the software will think that these indicate the end of a
program line. Intel Hex files contain no “>” characters, so there is no problem.
If you want to wait for the “>” character, in Procomm Plus, from the Setup menu, select
Terminal Options, then Protocol Options, ASCII Options, and set the pace character to 62.
Character pacing and line pacing can be 0. In the Windows terminal, select Settings, then
Text Transfers, One Line at a Time, and enter “>” under Wait for Prompt String. Other
software should have similar abilities.
If you wish, you can use BASIC-52’s (F)PROG command to store the program in NV
memory so it’s available without having to upload each time.
To use Listing B-1 or B-2, run the program and, at the prompt, use your communications
software to upload your object file. The file will load into the locations specified by your
source file. The program will display error messages if it has problems with the uploading.
For proper calculation of the programming-pulse width in Listing B-2, set BASIC-52’s
XTAL operator to match your crystal’s frequency.
If the file loads successfully, you’re ready to test it. Connect a logic probe to pin 1 on the
8052, or set a voltmeter to measure the voltage from pin 1 to pin 20 (ground) on the chip.
To call your subroutine, enter and run this BASIC-52 program:
The Microcontroller Idea Book 225