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Open source ARM Debugger
#199214
Hi all,

I am extremely new to OpenOCD so please be patient with me.

I have set up a OpenOCD Raspberry Pi in bit-banged SWD mode. I am flashing EFM32 chip. I am able to flash the chip using this command:
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[code]sudo openocd -f interface/raspberrypi2-native.cfg -c "transport select swd; bcm2835gpio_swd_nums 25 24; bcm2835gpio_srst_num 18; set CHIPNAME efm32; source [find target/efm32.cfg]; adapter_nsrst_assert_width 100; adapter_nsrst_delay 100; reset_config srst_nogate;" -c "init; reset halt; sleep 100; flash write_image erase fw.hex; sleep 100; reset run; shutdown"
Now I want to move further and integrate OpenOCD into the programming rig - add a button and some indication leds. Basically all I want is to know if OpenOCD was successfull in flashing the chip. To do all of this I want to integrate OpenOCD into some kind of scripting environment. I was thinking of starting OpenOCD as a server and then communicating with it via TCL from a Python script, however, I am not sure how to implement it properly.

Here is what I did:

I am starting OpenOCD with this config file:
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proc flashme {} {
   reset init
   reset halt
   wait_halt
   flash write_image erase fw.hex
   reset run
}

source [find interface/raspberrypi2-native.cfg]
transport select swd

bcm2835gpio_swd_nums 25 24
bcm2835gpio_srst_num 18
adapter_khz 1

set CHIPNAME efm32
source [find target/efm32.cfg]

adapter_nsrst_assert_width 100
adapter_nsrst_delay 100
reset_config srst_nogate

init
Then I try telnetting to it and issuing a 'flashme' command. The problem is - If I am connected to the target during the OpenOCD startup, I can issue the flashme command from telnet and everything works fine:
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Connected to localhost.
Escape character is '^]'.
Open On-Chip Debugger
> flashme
target halted due to debug-request, current mode: Thread 
xPSR: 0x01000000 pc: 0x0fe10000 msp: 0x20000400
target halted due to debug-request, current mode: Thread 
xPSR: 0x01000000 pc: 0x0fe10000 msp: 0x20000400
auto erase enabled
detected part: EFR32MG1B Blue Gecko, rev 152
flash size = 256kbytes
flash page size = 2048bytes
wrote 262144 bytes from file fw.hex in 8.524932s (30.030 KiB/s)
but If I connect the target after OpenOCD startup, I get these errors:
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Connected to localhost.
Escape character is '^]'.
Open On-Chip Debugger
> flashme
SWD DPIDR 0x2ba01477
Could not find MEM-AP to control the core
Target not examined, reset NOT asserted!
in procedure 'flashme' 
in procedure 'reset' called at file "openocd.cfg", line 2
in procedure 'ocd_bouncer'


> flashme
efm32.cpu: hardware has 6 breakpoints, 4 watchpoints
openocd.cfg:5: Error: invalid subcommand "write_image erase fw.hex"
in procedure 'flashme' 
in procedure 'flash' called at file "openocd.cfg", line 5
> 
What am I doing wrong? Can someone provide me some guidance on how can I achieve what I want - get feedback from OpenOCD if the flashing was successful?