Content originally posted in LPCWare by pdavenport on Mon Aug 04 19:12:26 MST 2014
Hi,
I have been working on a project with the lpc1769 microcontroller and have had a terrible time getting my custom hardware to program. In prototyping I have played with the mbed and the LPCxpresso develoupment boards for the lpc1769. These have worked fine, the LPCxpresso software worked as expected and I designed our custom hardware to basically be the same as the LPCxpresso target side of the board with a header for programming that is identical to the header used for programming the target side of the dev-board.
But the system refuses to recognize. I have also tried with multiple other tools. The only other thing that has had any success is using a bus pirate to do ISP over the UART. But whenever this starts working it will stop working after a short period of time. I believe that there is some sort of hardware problem in my design but I cant isolate it.
I attached a picture of the applicable page of my schematic, everything else is just peripheral stuff. I am doing development from a windows 7 pro laptop, with a working LPCxpresso development board as the programmer (by cutting the solder jumpers and connecting to my hardware). The hardware has been tested and no shorts are apparent. I am powering the board off of the programmer (LPC-Link) and only populated the components that are necessary for booting the chip (decoupling caps, main oscillator, and pull ups on the ISP enable pin and reset lines).
As I said before I am able to power up and talk to the chip through the UART auto baud ISP but after playing with that for a little bit the chip stops responding. I have tried this on a couple different units of the board and am sort of at a dead end. At no point have I been able to get SWD or JTAG to work from the LPC-Link or any other tool.
Any suggestions would be very much appreciated,
Peter
