DL11.EXE

dl11.exe is a utility program for downloading and configuring the 68HC11 series of microcontrollers. This document will describe how to use the features of the program.

Click the following link to download the file: dl11.exe

System Requirements: Windows 95/98/NT/2000/XP

Size: 53kb

Type: Command line program

dl11 supports several options via the command line. The options, which can be viewed using no arguments to the program, consist of:

Basics of how the program works

The HC11 series of parts have a special set of internal instructions called Bootstrap mode. In Bootstrap mode, the chip accepts a program coming in on the serial port. This program is stored starting at address $00, and usually extends to address $FF. Once the program has been downloaded, the CPU jumps to address $00 and starts executing code.

dl11 works by sending the CPU a special program called a talker file. The talker file is a small utility program that accepts commands to read and write memory. It can read and write either RAM or EEPROM. This small program occupies the first 256 bytes of RAM. It needs pretty much all 256 bytes, so you shouldn't plan on using this memory while downloading code. The talker program communicates with your PC at 9600 baud.

Once dl11 finishes programming your board, you can reset your chip, and it should start running the code you downloaded (assuming you set the reset vectors correctly). The talker program only needs the RAM during download. On reset, the talker program is erased from memory.

dl11 is a 'command line' program, meaning it runs in a text window. It requires Windows 95 or higher to function. Windows 95/98/NT/2000/XP should work just fine. You also need an available serial port.

The Command Line Switches

Each of the options and arguments are documented next. A couple of general notes:

Sample Sessions

The following sample sessions should give you the jist of how the program works.

Simple download of a program

Assuming you have a BotBoard Plus attached to COM1 of your PC, then a simple sample session looks like the following.

< Set your board to LOAD mode using the switch>

<Press the RESET button>

The first three lines are the version and signon banner. The program then informs us that it is reading in the input file "d:\src\nl11\memtest.s19" which is the full path to the input file. The download of the talker is then reported. The talker downloads at 1200 baud, so it might take a few seconds. The >S means the initial sync byte of $FF is sent. >W means the talker program itself has been written. The >R means the talker is being read back to verify its validity. The >OK! means it verified.

Next comes each section of the S19 file. Memory ranges are written in chunks. This program has two chunks: F800-FD23 which is EEPROM, and FFFE-FFFF which is also EEPROM. Your particular S19 file may be different.

Download Completed means life is good, and you can run your program by selecting run mode on your target board and resetting.

Download and Debug

The following shows a common use for dl11.exe, namely downloading code and using the serial port for debugging the output. dl11.exe features a very simple 9600 baud terminal mode that you can use to do the download/debug cycle many times. In the following example, dl11 performs the download, but because of the -T switch, it enters terminal mode.

Notice the '>' character that printed out. This is normal. It is the 'talker' program prompt character, and will usually appear. At this point, dl11 is running as a simple terminal program. As you can see, there are 3 function keys available. F1 will print a help message. F2 exits the program, and F3 causes the download to start again. In this example, I reached over, switched the BotBoard Plus into run mode, and pressed the reset button on my target board.

All of that output was from the memtest.s19 program. At this point, I made a change to my HC11 code, and recompiled memtest.s19. I now want to reload it. I have reached over and set the BotBoard Plus to LOAD mode, and pressed the reset button. On my PC's keyboard, I just pressed function key F3 to restart the download.

Note that I can stay in this mode of repeating downloads over and over. Don't forget to reset your target board first, or the program will exit due to a communication error.

Verifying the contents of memory

Another useful example is when you have an S19 file and a target board. You would like to verify that the contents of the memory on the target board contains the contents of the S19 file. You can use the -v command. Note that this only compares the contents of the S19 file against memory. It says nothing about memory locations not found in the S19 file.

Reading the contents of memory

Lets assume what you really want to do is save the contents of memory away to a file. dl11 can do that for you. It saves the file in S19 format, so if needed, you could reload it later.

Doing Lots of Stuff

In the next example, I am going to download memtest.s19 again. I am also going to do some extra steps. I am doing a BULK erase of EEPROM. This speeds up the reprogramming of the flash when you are updating to an entirely new program. I have set the memory map to be for an 811E2 part. I have also decided to save the existing memory range 0xf800:0xffff into a file called memout.s19 using the -r command. This reads the memory before doing the bulk erase or reprogramming. You can use the -r command by itself.