olimex Sometimes is is quite handy to have access to a JTAG interface to look more deeply into problems.  The weapon of choice is an Olimex ARM-USB-OCD-H JTAG in combination with OpenOCD 0.8.0. First we will need to install OpenOCD.

  1. apt-get install libftdi-dev
  2. Download and extract OpenOCD 0.8.0
  3. run ./configure
  4. run make && make install

This should give you an OpenOCD installation with the following configuration:

OpenOCD configuration summary ————————————————– MPSSE mode of FTDI based devices yes (auto) ST-Link JTAG Programmer yes (auto) TI ICDI JTAG Programmer yes (auto) Keil ULINK JTAG Programmer yes (auto) Altera USB-Blaster II Compatible yes (auto) Segger J-Link JTAG Programmer yes (auto) OSBDM (JTAG only) Programmer yes (auto) eStick/opendous JTAG Programmer yes (auto) Andes JTAG Programmer yes (auto) Versaloon-Link JTAG Programmer yes (auto) USBProg JTAG Programmer yes (auto) Raisonance RLink JTAG Programmer yes (auto) Olimex ARM-JTAG-EW Programmer yes (auto) CMSIS-DAP Compliant Debugger no

Now its time to check if a debugger connection can be established. As the JTAG is usb based you should see it via lsusb.

Bus 002 Device 005: ID 15ba:002b Olimex Ltd. ARM-USB-OCD-H JTAG+RS232 Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.00 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x15ba Olimex Ltd. idProduct 0x002b ARM-USB-OCD-H JTAG+RS232 bcdDevice 7.00 iManufacturer 1 Olimex iProduct 2 Olimex OpenOCD JTAG ARM-USB-OCD-H iSerial 3 OLWI19GT bNumConfigurations 1 […]

At this point OpenOCD should be able to connect to the JTAG. For the beginning you only need to provide the interface and target scripts. In my case the following works.

[email protected]:~$ sudo openocd -f interface/ftdi/olimex-arm-usb-ocd-h.cfg -f target/imx6.cfg Open On-Chip Debugger 0.8.0 (2014-05-05-11:14) Licensed under GNU GPL v2 For bug reports, read http://openocd.sourceforge.net/doc/doxygen/bugs.html Info : only one transport option; autoselect ‘jtag’ Warn : imx6.sdma: nonstandard IR value adapter speed: 1000 kHz Info : clock speed 1000 kHz Info : JTAG tap: imx6.dap tap/device found: 0x4ba00477 (mfg: 0x23b, part: 0xba00, ver: 0x4) Info : TAP imx6.sdma does not have IDCODE Info : JTAG tap: imx6.sjc tap/device found: 0x2191e01d (mfg: 0x00e, part: 0x191e, ver: 0x2) Info : imx6.cpu.0: hardware has 6 breakpoints, 4 watchpoints Info : number of cache level 1 Info : imx6.cpu.0 cluster 0 core 0 multi core