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LPC1764 Assistance


New Member
Hey guys, I made a post on LPCware.com, but their forum isn't the best (takes forever to get a response and to get a post through since it must go through moderation each time).

Here is the link to the post:


I made the following response (which at this time is still in the process of being posted...):

I'm not sure if it is the crystal (I have a spare on hand) and it was working fine before. Either way, I am now getting either one of two errors:

05: File load failure: EM(12). System rejected access at location 0x10000000 - verify Population of memory and peripherals
I looked into possible fixes for this and found this:

ISP pin and vector cache fix.

I'm not sure if I did the ISP fix right. I grounded reset and grounded the ISP pin (pin 53) and then held reset high. It didn't work and I'm not sure if I did that right. Also, I tried changing vector cache to true by right clicking on the project going to Launch configurations->Edit current and under "C/C++ (code Red)MCU Application" I selected my project and clicked on the debugger tab and under "Configuration Option" I selected True under vector cache.

However, upon trying to program to flash I get either the previous error before or:

02: Failed on connect: Ep: (01). Target marked as not debuggable.
And, the popup window still says vector cache is false when I set it to true using the methods above. So, I may have done it wrong...
So, if anyone has any experience with the LPC1764, LPC expresso, or has an idea as to how to fix this it would help a lot. Thanks.


Well-Known Member
I'll try, but most of this will be speculation. I've only used full JTAG with the LPC17xx, but I've used SWD with the LPC11xx and 13xx. Where did you get that schematic from, because the SWD connections are wrong? Pin one should be VDD, but instead its got a resistor going to TRST. Pin 10 should be nRESET. TRST is a JTAG pin and should be pulled up, 10k.


New Member
The connections I have for SWD are as follows:

LPC1768 Pin # <------> LPC-Link 2 Pin #
(SWDIO) 3 <------> 2 (SWDIO)
(SWCLK) 5 <------> 3 (SWCLK)
(RESET) 17 <------> 6 (RESET)
All VDD <------> 1 (3v3)
All GND <------> 8 (GND)

*In between all VDD and GND I have a 100nF capacitor

Thank you for the repy, I placed a 10k pullup on pin 4 (TRST of LPC1768). I believe the rest of my connections are correct (they're different from above schematic) as it was working before. If you see anything else out of place though please let me know. I think the one thing that is missing from the schematic is a 10K pullup resistor on pin 53 (p2.10) for ISP pin.

I keep switching between the two errors mentions above. One method was ISP pin fix (hold pin low upon startup), another was setting vector cache to true, and the last was programming via UART to unbrick the microcontroller.

I'm going to try the UART fix and see if it works. So far, I don't like how cumbersome ARM is compared to PIC32. I really never ran into this issue once I had the proper hardware and software with PIC32, which is why I am a bit confused at this point.


I am having difficulty with flash magic. It keeps giving me an "autobaud rate" error. I looked into it a bit and it could be the connections. The way I have it connected it as follows:

LPC1768 Pin # <------> FTDI RS232 3v3 Pin #
All VSS <------> 1 (GND)
All VDD <------> 3 (Power)
(RXD1) 74 <------> 4 (TXO)
(TXD1) 75 <------> 5 (RXT)

I have made to select the right part (LPC1764) and I have imported the hex file that was taken from the build of interest using LPC Expresso.


I made my own schematic in attempts to clear up any confusion with my connections.

Last edited:


New Member
Got it working. It was a soldering/ pin issue. Also, quick note. In the above schematic I accidentally connected RESET to pin 7 and not 6. It was correct in the circuit I was troubleshooting, but incorrect in the above schematic (just in case anyone wants to use it).

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