Motorola CMD11E1 manual Assembling source code, AS11 HELLO.ASM -l cre s HELLO.LST

You should write your source code using a standard ASCII text editor. Many powerful code editors are available or you can use the free EDIT or NOTEPAD programs that come with your computer. Once your source code is written and saved to a file, you can assemble or compile it to a Motorola S-Record (hex) format. This type of output file usually has a .MOT, .HEX or .S19 file extension and is in a format that can be read by the programming utilities to be programmed into the CMD11E1 board.

It's important to understand your development board's use of Memory and Addressing when writing source code so you can locate your code at valid addresses. For example, when in "debug" mode, you should put your program CODE in External RAM. In assembly language, you do this with ORG statements in your source code. Any lines following an ORG statement will begin at that ORG location, which is the first number following the word ORG, for example: ORG $2000.

You must start your DATA (or variables) in a RAM location unused by your program, for example: ORG $1040. When finished debugging, you must change these ORG statements so that your program is moved to a valid EEPROM area - somewhere after hex E000 (or 8000 on a 32k board). Do this by putting an ORG $E000 in front of your Program CODE. Data may remain where it is or be moved down to internal RAM starting at ORG $0000. You must also program the STACK register somewhere at the top of your available RAM, for example hex 1FF. Do this with this instruction as the first instruction in your program code: LDS #$01FF.

A look at the example programs on the disk can make all of this clearer. If you're using a Compiler instead of an assembler, consult the compiler documentation for methods used to locate your code and data.

Source code created to run under the buffalo monitor environment will be slightly different than code written for stand-alone operation. The buffalo monitor contains interrupt and RESET vectors that your code must provide when it's no longer running under the monitor. See the Programming External EEPROM section for more information on this.

Assembling source code

An example program called “HELLO.ASM” is provided under the \EXAMPLE directory.

You can assemble your source code using command line tools under a DOS prompt by typing:

AS11 HELLO.ASM –l cre s >HELLO.LST

Most compilers and assemblers allow many command line options so using a MAKE utility or batch file is recommended if you use this method.

The AxIDE utility software provided with this board contains a simple interface to the free assembler. Use it by selecting "Build" from the menu. This will prompt you for the file to be assembled.

DO NOT use long path names (> 8 characters). The free assembler is an old DOS tool that does not recognize them.

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