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- Path: sparky!uunet!dtix!darwin.sura.net!mojo.eng.umd.edu!pandora.pix.com!stripes
- From: stripes@pix.com (Josh Osborne)
- Newsgroups: comp.arch
- Subject: Re: Why would you like a debugger (Was: What would you like in a debugger?
- Message-ID: <Bt0Btr.57n@pix.com>
- Date: 15 Aug 92 04:15:26 GMT
- References: <1992Aug7.151937.14321@linus.mitre.org> <341@moene.indiv.nluug.nl>
- Sender: news@pix.com (The News Subsystem)
- Organization: Project GLUE, Merriversity of Uniland, College Purgatory
- Lines: 41
- Nntp-Posting-Host: pandora.pix.com
-
- In article <341@moene.indiv.nluug.nl> toon@moene.indiv.nluug.nl (Toon Moene) writes:
- [...]
- >one of these (I would be interested in hearing how people debug embedded
- >systems, however). For all other sorts of programming: write critical
- >variable's values to the screen [...]
-
- I write video games, they are sort-of real time, and definitally embedded
- systems. Sometimes I write veriables to UART port A (port B is used to
- talk to the sound device). Much of the time I use ICE (In-Circuit Emulator).
- The ICE I have emulates my CPU and a goodly chunk of memmory (which can
- be configured read-only - to simulate ROM without forcing you to re-burn
- EEPROMS after each compile, or read-write which I haven't needed to do).
-
- In many ways using ICE is alot easyer then normal debugging. It is 100%
- real-time, even if you are having it do complex stuff. It can have breakpoints
- (or other actions) on data (reads or writes, or more complex things) again
- with no speed loss. It can give you a complete history of the last N
- instructions executed (where N is at least 150 for me), and all the bus cycles
- executed.
-
- The ICE I have has downsides.
- Normally I run my code until it hits a breakpoint, use the trace data to
- figure out what source I was executing, and use my brain for the rest.
- A source debugger would let me know alot faster. If I need to look at
- a structure element I have to figure out it's offset by hand and find it.
- If I want another ICE (say for testing multi-board games, or testing a
- non-devlepment game (i.e. a real test-unit), or whatever) it costs over
- $10k.
-
- There does exist ICE that will do (at least some) source level debugging.
- I would love some. As it is, I would rathere run UPS on my code then use
- ICE, except I can't afford the speed hit...
-
- (So what do I want in a software debugger? Mostly just a C++ version
- of UPS, and data watchpoints... what do I want in ICE? The same :-)
- --
- stripes@pix.com "Security for Unix is like
- Josh_Osborne@Real_World,The Multitasking for MS-DOS"
- "The dyslexic porgramer" - Kevin Lockwood
- We all agree on the necessity of compromise. We just can't agree on
- when it's necessary to compromise. - Larry Wall
-