DAPCmdr

J-LINK Commander like tool for JLink and DAPLink, adding HardFault diagnosis and SVD-based peripheral register access.

To run this tool, you need python 3.6+ and prompt_toolkit 3.0+.

To use DAPLink, you need additional pyusb for CMSIS-DAPv2 and another usb-backend for CMSIS-DAPv1 (hidapi or pywinusb for windows, hidapi for mac, pyusb for linux).

√ meaning file exists, × meaning not.

Basic Command

memory read/write

Read  8-bit items. Syntax: rd8 <addr> <count>
Read 16-bit items. Syntax: rd16 <addr> <count>
Read 32-bit items. Syntax: rd32 <addr> <count>

Write  8-bit items. Syntax: wr8 <addr> <value>
Write 16-bit items. Syntax: wr16 <addr> <value>
Write 32-bit items. Syntax: wr32 <addr> <value>

memory read/write to/from file

Save target memory into binary file.
Syntax: savebin <filepath> <addr> <NumBytes>

Load binary file into target memory.
Syntax: loadbin <filepath> <addr>

core register read/write

DAPCmdr > wreg r0 12345678

DAPCmdr > regs
R0 : 12345678    R1 : 0000000A    R2 : 00146BAB    R3 : 044AA200
R4 : 0000000A    R5 : 40011000    R6 : 20000000    R7 : 40010800
R8 : 00008000    R9 : 20000160    R10: 00000000    R11: 00000000
R12: 00000001    SP : 20000420    LR : 08000247    PC : 08000226
MSP: 20000420    PSP: 20000800    XPSR: 01000000
CONTROL: 00 (when Thread mode: privileged, use MSP)

device control

reset
halt
go

HardFault Diagnosis

halt and regs command will detect if HardFault happened, if so, they will analysize and print the cause, Stack Content and CallStack.

DAPCmdr > halt
R0 : 20000000    R1 : 00000001    R2 : 00000000    R3 : 08000DA9
R4 : 08000E08    R5 : 08000E08    R6 : 00000000    R7 : 00000000
R8 : 00000000    R9 : 20000160    R10: 00000000    R11: 00000000
R12: 00000000    SP : 200003E0    LR : FFFFFFF9    PC : 08000422
MSP: 200003E0    PSP: 20000800    XPSR: 61000003
CONTROL: 00 (when Thread mode: privileged, use MSP)

a divide by zero has taken place (can be set only if DIV_0_TRP is set)

Stack Content @ 0x200003E0:
200003E0:  20000000 00000001 00000000 08000DA9 00000000 080001C9 0800015C 61000000
20000400:  00000000 00000000 00000000 00000000 00000000 00000000 00000000 08000E08
20000420:  08000E08 080001C9 00000000 08000DA9 08000E08 08000D81 FFFFFFFF FFFFFFFF

Call Stack:
0x0800015C  SerialInit
0x080001C9  main

to print CallStack, you need to specify disassembling file using path dis command.

dis

display CallStack information coming from disassembling file.

disassembling file can be built by command below:
MDK: fromelf --text -a -c -o "$L@L.dis" "#L"
IAR: ielfdumparm --code --source $TARGET_PATH$ -o $TARGET_PATH$.dis
GCC: objdump -d $@ > $@.dis

SVD-based peripheral register access

svd-based peripheral register read and write
register read:        sv <peripheral>.<register>
register write:       sv <peripheral>.<register> <hex>
register field write: sv <peripheral>.<register>.<field> <dec>

when typing peripheral/register/field name, DAPCmdr will do auto-completion.

Other Command

path

display path, Syntax: path
set JLink_x64.dll, Syntax: path dll <dllpath>
set svd file path, Syntax: path svd <svdpath>
set dis file path, Syntax: path dis <dispath>

when typing path, DAPCmdr will do auto-completion.

env

DAPCmdr > env
%pwd%     C:\Users\WMX\Desktop
%home%    C:\Users\WMX
%Packs%   C:\Programs\MDK\Arm\Packs

these variables can be used in path typing.

vsmawoex / DAPCmdr