CodeWarrior for FreeScale 尝试使用 56800E 模拟器调试简单程序
我刚刚开始学习 FreeScale DSC（MC56F800x 系列）。我使用 Windows 上的 AVR Studio 和 Linux 上的 Eclipse 和 avr-gcc 完成了一些 AVR 工作。 CodeWarrior 只是不那么直观。
现在我正试图调试一个简单的程序。我使用内置模拟器启动调试器，但它从未到达 main() 的第一行。相反，它似乎陷入了一些初始化代码（MC56F8006_init.asm）中，特别是这一行：
;; Loop until OCCS_STAT[LCK0] = 1
wait_for_lock:
brclr #OCCS_STAT_LCK0,x:>OCCS_STAT,wait_for_lock
我已经让它运行了很长一段时间，但它永远不会超越这一点。显然是在等待什么，但是什么？你可能会认为模拟器会正常工作......啊。也许我可以更改一些选项以使其通过这一步？
我将继续挖掘，如果我先找到它，我会在这里发布答案。
更新：
以下是我发现的内容：
OCCS
- 片上时钟合成
brclr
- 如果位清除则
转移 该指令循环直至 OCCS_STAT LCK0 被置位。该寄存器表示片上振荡器的 PLL 已锁定（等待时钟稳定）。
我仍然不确定为什么模拟器会在这条线上永远旋转，以及如何在不破解初始化代码（这是代码库的一部分而不是在我的项目中）的情况下解决这个问题。
I'm just getting started learning FreeScale DSCs (MC56F800x series). I've done some work with AVRs using both AVR Studio on Windows and Eclipse and avr-gcc on Linux. CodeWarrior is just not as intuitive.
Right now I'm stuck trying to debug a simple program. I start the debugger using the built-in simulator, but it never reaches the first line of main(). Instead it seems to get stuck in some initialization code (MC56F8006_init.asm), specifically this line:
;; Loop until OCCS_STAT[LCK0] = 1
wait_for_lock:
brclr #OCCS_STAT_LCK0,x:>OCCS_STAT,wait_for_lock
I've let it run for quite a while and it never gets past this. It's obviously waiting for something, but what? You would think the simulator would just work... argh. Maybe there's some options I can change to make it pass this step?
I'm going to keep digging and will post an answer here if I find it first.
Updates:
Here's what I've found:
OCCS
- On Chip Clock Synthesis
brclr
- Branch if Bits Clear
The instruction loops until OCCS_STAT LCK0 is set. This register means the on-chip oscillator's PLL has locked (waits for clock stabilization).
I'm still not sure why the simulator spins forever on this line, and how I can solve this without resorting to hacking up the init code (which is part of the code library and not within my project).
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我不熟悉该部件或模拟器，但该模拟器似乎仅是指令集，并且不模拟 PLL 硬件。
在大多数嵌入式开发系统中，运行时启动代码作为源代码提供，您可以修改它（或者更确切地说，在项目中制作本地副本，然后汇编和链接它以覆盖默认启动）。或者，您可以简单地在此循环中放置一个断点，然后前进程序计数器寄存器以使其脱离循环。在许多调试器中，可以将脚本附加到断点以自动执行此操作。
I am not familiar with the part or the simulator, but it seems likely that the simulator is instruction-set-only and does not simulate the PLL hardware.
In most embedded development systems, the run-time startup code is provided as source and you could modify it (or rather make a local copy in your project and assemble and link that to override the default start-up). Alternately you could simply place a breakpoint in this loop, and advance the program-counter register to get it out of the loop. In many debuggers it is possible to attach a script to a breakpoint to do this automatically.