With USB goes medical I have a serial-to-USB (CDC) support for my TWR-S08MM128 board. What makes these devices targeted for medical applications interesting for other applications are features like bootloader support and a CRC (Cyclic Redundancy Check) engine. But how can I generate the required CRC numbers with MCU10?
Maybe this situation is familiar to you: My embedded software stopped in the field. I am in front of it, hooked up with my laptop and debugger. And I see: indeed, it has a problem. Maybe just a one-time-thing? Maybe I do a reset and things will work as expected? Not really, according to Debugging Rules.
The thing is this: I’m in a situation which requires some deep investigation. But I do not have the time now. Or my boss, the boss-boss or the customer are standing behind me asking all the good questions for which I don’t have an answer. So in this situation it would be great if you could take a dump of the device memory, reset that board, move on and investigate what happened offline? Here are several ways how to do this…
In eclipse and CodeWarrior for MCU10 the usual thing I do is:
If I need to program another board with the same binary, then I download it to that board too. Fine. But what if I want to skip point 1 and 2? What if I do not have or want a project? All what I have (and need) is a binary file, and I want is to flash that file to my boar. By pressing a button.
Sometimes my embedded application is not doing what I want it to do. I can solve many problems with normal ‘step/stop mode debugging‘: setting breakpoints, step, stop, inspect data, and so on. But not always. If a piece of code is changing a global variable unintentionally, I do not know where to set my breakpoint. Something is changing my variable, and I have no clue from where. It could be a dangling pointer, a stack overflow or something similar which I cannot track down with code breakpoints. What I need is a breakpoint on data: watchpoints!
In many cases I do a full erase-flash-debug cycle: I get my embedded microcontroller flash completely erased and then programmed with my application. Well, that does not work that way if I program with a bootloader. Yes, I can flash the bootloader and then load my target application with the bootloader, but that’s not the scenario I want to use in the development phase. I want to flash my application and keep the bootloader on the target. This means: I need to do erase and program a part of the memory. But how to do this?
It happens to me that I run into a really, really nasty problem. I spend hours (if not weeks) to get it resolved. Strong coffee and the problem keeps me up at long nights. I think every embedded system engineer knows what I’m talking about. Yeah, most of the time it is my fault or an oversight. But once in a while I’m convinced that I have found a real bug. Then I report it back to the vendor to fix it. I hope my report will prevent another engineers to run into the same problem. Or that I learn something else as a by-product. Oh yes….
With “Eclipse and PC-lint: Linticator” I have a plugin to lint my sources in a comfortable way. But I can do this as well without a plugin. For this I use a batch file with a build configuration, plus settings to get the PC-lint messages into the Problems view. Yes, this does not sound easy, but is very doable and straight forward once I have set it up. It gives me complete control on every little detail. Here is how I do it… Continue reading
The eclipse based CodeWarrior for MCU10.2 comes with many unique extensions of the eclipse platform, implemented by Freescale. One of these featured mentioned in my post is the ability to inspect the registers in an offline mode: The Offline Register view. How is this different from the Registers view?
PC-lint from Gimpel has set the standard for static code analysis: it is used by many companies developing safety critical applications. Additionally PC-lint can check the MISRA rules which are standard for many coding guide lines. PC-lint has detected many subtle bugs in my sources. Thank you, PC-lint!
CodeWarrior classic provided a plugin for the PC-lint compiler: To bad that this does not exist in the eclipse based CodeWarrior. You might think that given PC-lint so popular, there should be an eclipse plugin available? Yes, there are many attempts on this: all of them did not work well enough for me. The good news: There is the Linticator eclipse plugin. The bad news: it is not for free.
My post in “An error occurred…”: Applied Debugging Rules gives some hints about how to isolate and solve some debugging problems. But here is a case where the tips did not help: I had this dialog with “Failed to resume target process” for my HCS08 project again:
MCU on Eclipse 