I'm using J-Link ARM + J-Flash ARM V4.28c to download firmware on a LPC1754 (Cortex M3 from NXP).

I'm using the following command line inside a makefile:

"JFlashARM.exe -open$(OUTDIR)/$(TARGET).hex -connect -erasesectors -program -verify -startapp -disconnect -exit"

My "problem" is after "startapp" commnad is issued J-Flash freezes for about 25 seconds and only after that new firwmare starts to execute. During these 25 seconds seems to me tha J-Flash is trying to establish communication with J-Link or J-Link is trying to synchronize with LPC1754.

Could someone tell if it is possible to reduce this delay/freeze time between download end and starapp finish.

Regards,

Marcio Ribeiro

Hi Alex I have one more thing to add to this issue:

when I use "JLinkGDBServer.exe" to download firmware I have my program running almost instantaneously.

Here is the contents of my makefile related on to this issue:

JLRUNFILE = lpc1754_run.jlink
run: elf
arm-none-eabi-gdb.exe --command=$(JLRUNFILE) --symbols=$(OUTDIR)/$(TARGET).elf --exec=$(OUTDIR)/$(TARGET).elf

and here is the contents of the gdb script file`:

target remote localhost:2331
monitor interface JTAG
monitor endian little
monitor flash device = lpc1754
monitor flash breakpoints = 1
monitor flash download = 1
monitor speed 12000
load
monitor reset 0
monitor go
disconnect
quit

Though this solution worked for me I like to know why JFlash works so slow when I need download and getting my firmware running (appstart).

Regards,

Marcio