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Re: eclipse arm openocd download fails

 by JJ ¦  Sat Feb 24, 2018 11:09 pm ¦  Forum: Everything ARM and LPC ¦  Topic: eclipse arm openocd download fails ¦  Replies: 1 ¦  Views: 905

In a different terminal, telnet to localhost:4444 and halt the target with "reset halt"

openocd doesn't halt the target when it connects, and gdb can't connect with the target running.

Re: 10 pin ARM Cortex JTAG

 by JJ ¦  Thu Feb 15, 2018 8:52 pm ¦  Forum: Everything ARM and LPC ¦  Topic: 10 pin ARM Cortex JTAG ¦  Replies: 2 ¦  Views: 628

Looking at the schematic for the Olimex 20-to-10 adapter, they run this through an unpopulated resistor, so I guess I can just ground it. (That's the adapter I use.)

What about GNDDetect? Another pin to just ground?

Re: 10 pin ARM Cortex JTAG

 by JJ ¦  Thu Feb 15, 2018 8:33 pm ¦  Forum: Everything ARM and LPC ¦  Topic: 10 pin ARM Cortex JTAG ¦  Replies: 2 ¦  Views: 628

Also, I'm concerned if it's an ISP enable it would be held high unless trying to enter ISP. If I ground it this would not be so great and might cause the programmer to shutdown on overload if it shorts (FT2232R I believe is what the FS2 uses, not sure if it's buffered).

10 pin ARM Cortex JTAG

 by JJ ¦  Thu Feb 15, 2018 8:30 pm ¦  Forum: Everything ARM and LPC ¦  Topic: 10 pin ARM Cortex JTAG ¦  Replies: 2 ¦  Views: 628

Anyone know what to do with the KEY signal on a 10 pin connector? I've seen suggestions it can just be grounded, but I'm concerned this might short out a programmer. (I use a Flyswatter 2 with OpenOCD) In the past I've used 20 and 14 pin JTAG but would like to reduce it to 10 to save board space (wi...

Re: EINTx on LPC2148 problem

 by JJ ¦  Sat Mar 20, 2010 2:52 pm ¦  Forum: Everything ARM and LPC ¦  Topic: EINTx on LPC2148 problem ¦  Replies: 4 ¦  Views: 1329

I find it easier to have a common vector and dispatch, but use the VIC to store a pointer to device context for the device. (Including func ptr/vtable entry to the device interrupt handler.) This means you load up the VIC with addresses of device structures but set the vector itself not to read from...

Re: C++ on a LPC2378

 by JJ ¦  Sat Mar 20, 2010 1:52 pm ¦  Forum: Everything ARM and LPC ¦  Topic: C++ on a LPC2378 ¦  Replies: 8 ¦  Views: 2966

You don't really need libstdc++ if you don't use RTTI or exceptions. You can disable them by compiling with -fno-rtii -fno-exceptions. You can define your own new/delete to wrap malloc; you'll probably want this anyway since if you compile without exceptions new will return NULL on allocation failur...

 by JJ ¦  Sun Jan 31, 2010 12:23 pm ¦  Forum: Everything ARM and LPC ¦  Topic: JTAG interface compatibility ¦  Replies: 2 ¦  Views: 771

I've been using a Flyswatter, which uses board-specific adapters. There's one for the BeagleBoard. It's a very nice little debug/pgm board and the use of adapters makes it a lot more versatile than most others. It's pretty easy make y...

 by JJ ¦  Thu Jan 21, 2010 7:57 am ¦  Forum: Everything ARM and LPC ¦  Topic: Cortex-M3 Debugger & Tools ¦  Replies: 28 ¦  Views: 13521

The CM3 "virtue" is made with the reversed disciplines; extremely short pipleline and cache less memory architecture. Note that longer pipeline and complicated cache mechanics have been the essentials of modern ultra fast processors. The cacheless microcontrollers are fantastic when coupled with fa...

 by JJ ¦  Thu Jan 21, 2010 7:42 am ¦  Forum: Everything ARM and LPC ¦  Topic: 9V on 3.3V in, did I blow it up ¦  Replies: 13 ¦  Views: 2079

It's somewhat possible you only fried the power LED. See if the CPU still runs.

 by JJ ¦  Tue Jan 12, 2010 7:01 pm ¦  Forum: Everything ARM and LPC ¦  Topic: ConfigurePLL throws ¦  Replies: 2 ¦  Views: 1028

The assembly code looks like nonsense. It looks like you relocated your code to run out of flash but never actually flashed the device.

 by JJ ¦  Sun Jul 12, 2009 6:08 pm ¦  Forum: Everything ARM and LPC ¦  Topic: ARM development software ¦  Replies: 60 ¦  Views: 9161

By liability, I don't mean that related to the product built with the tool. I do mean that if the tool proves to be other than that represented, and has a flaw causing damages in the form of delaying the product completion, then with a commercial compiler, you have legal recourse to force them to c...

 by JJ ¦  Fri Jul 10, 2009 10:07 pm ¦  Forum: OpenOCD ¦  Topic: Breakpoints for programs running in Flash on OpenOCD ¦  Replies: 5 ¦  Views: 2624

It may also be that after the reset the CPU has run past the breakpoint already by the time it's reinstated.

 by JJ ¦  Fri Jul 10, 2009 10:02 pm ¦  Forum: Everything ARM and LPC ¦  Topic: How the GNU Assembler uses labels ¦  Replies: 3 ¦  Views: 2212

The two forms do the same thing, except =symbol automatically puts the reference in a literal pool. This can be issue with the vectors since there is no guarantee where the pool is placed, technically it might end up outside the mappable vector region.

 by JJ ¦  Mon Jul 06, 2009 8:56 pm ¦  Forum: Everything ARM and LPC ¦  Topic: ARM development software ¦  Replies: 60 ¦  Views: 9161

Code reusability is better with gcc as well. Your next project might be on say MIPS or Blackfin, and it's nice to be able to repurpose generic code with minimum fuss. It's also easier to use to unit test on an x86 system by mocking lower level drivers. Like a mock SD driver that returns sectors from...

 by JJ ¦  Sun Jul 05, 2009 11:51 pm ¦  Forum: Everything ARM and LPC ¦  Topic: Why did you choose ARM? ¦  Replies: 64 ¦  Views: 11926

Depends on what you mean by "video". If you mean shovel bits off a camera onto a network, an ARM SoC like the LPC2468 will do that just fine.

If you actually want to process the video you might want to look at e.g. Blackfin.