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--- jtag [2016/02/03 13:47] – [ST-Link v2 (clone)] add pinout kingkevin
+++ jtag [2017/04/25 14:04] – [ST-LINK V2 aluminium] kingkevin
@@ Line 1: / Line 1: @@
-Here I will describe my experiences with JTAG and how I use it.
+JTAG is a technology to test integrated circuits, mostly micro-controllers and CPUs.
+It allows to do hardware debugging: read/write memory, control I/Os, and debug running code.\\
-JTAG is a technology to test electronics.
+SWD is a more modern version of JTAG and only requires 2 pins instead of 4[+1].\\
-It allows to do hardware debugging: test I/O, flash firmwares, step through assembly code, ...
+SWJ is a combination of Serial Wire Debug (SWD) and JTAG.
+But they provide the same logical functions.
 On one side this functionality must be included in the target device.
-Most 32 bits micro-controllers and SoCs have it.\\
+The Debug Port is often called JTAG-DP for JTAG and SW-DP for SWD.
-On the other side you need a JTAG adapter so the host can speak to the device using the JTAG protocol.
+SWJ capable device include and often combine both, as the SWD signal pins SWDIO and SWCLK re-use the JTAG signal pin JTMS and JTCK (backwards compatible).
-JTAG adapters can go from cheap (<5$) to expensive (>1000$), depending on the quality of the hardware and software.
+Most 32 bits micro-controllers and SoCs have one of both (or both).
-===== JTAG adapters =====
+On the other side you need a SWJ adapter so the host can speak to the device using the JTAG and/or SWD protocol.
+SWJ adapters can go from cheap (<5$) to expensive (>1000$), depending on the quality of the hardware and software.
-These are the main JTAG adapters I am using.
+====== SWJ adapters ======
-==== ST-Link v2 (clone) ====
+These are the main SWJ adapters I am using.
+===== ST-Link v2 =====
 The [[http://www.st.com/web/catalog/tools/FM146/CL1984/SC724/SS1677/PF251168|ST-LINK/V2]] is from STMicroelectronics, and is very convenient to flash their STM8 and STM32 micro-controllers, such as the [[stm32f1xx|STM32 F1 series]].
+It supports JTAG, SWD, and SWIM (for STM8).
-I have two cheap clones:
+These SWJ adapters are based STM32F1xx ARM Cortex M3 micro-controllers.
-  * one from [[http://www.aliexpress.com/item/Free-Shipping-1SET-ST-Link-st-link-V2-for-STM8S-STM8L-STM32-Cortex-M0-Cortex-M3/1758613434.html|BAITE]]
-{{:jtag:dsc02404.jpg?0x100|device front}}
-{{:jtag:dsc02405.jpg?0x100|device back}}
-{{:jtag:dsc02403.jpg?0x100|PCB front}}
-{{:jtag:dsc02406.jpg?0x100|pinout sticker}}
-{{:jtag:st-link_v2_baite.svg?0x100|pinout}}
-^ STM32F103C8 signal ^ STM32F103C8 pin ^ adapter pin ^ adapter signal ^
-| PA7 | 17 | 1 | JRST |
-| AMS1117 |  | 2 | 3V3 |
-| USB VCC |  | 3 | 5V |
-| PA4 | 14 | 4 | JTCK/SWCLK |
-| PB11 | 22 | 5 | SWIM/SWDIO |
-| PA14 | 37 | 6 | JTMS |
-| USB GND |  | 7 | GND |
-| PA5 | 15 | 8 | JTDO |
-| PB6 | 42 | 9 | SWIM_RST |
-| PA6  | 16 | 10 | JTDI |
-| PB12,PB14 | 25,27 |  |  100 ohms |
-| PB5 | 41 |  | LED |
-the adapter pins are protected with a 220 ohms resistor.
-  * one [[http://www.aliexpress.com/item/Hot-Sale-1PCS-ST-LINK-Stlink-ST-Link-V2-Mini-STM8-STM32-Simulator-Download-Programmer-Programming/32343514985.html|more generic]]
-{{:jtag:dsc02407.jpg?0x100|device front}}
-{{:jtag:dsc02408.jpg?0x100|device back}}
-{{:jtag:dsc02415.jpg?0x100|PCB front}}
-{{:jtag:dsc02410.jpg?0x100|PCB back}}
-These devices use the Serial Wire Debug (SWD) protocol.
-This is newer variant of JTAG which requires only 2 signal lines instead of 4+.
-But but aware, they both have different pinouts on the connector.
-The second one offers 2 more power ports at the expense of JTAG TDI and TDO/SWO.
-These JTAG adapters are based STM32F1xx ARM Cortex M3 micro-controllers.
 And ironically enough I in turn use them to program and debug STM32F1xx ARM Cortex M3 micro-controllers.
@@ Line 58: / Line 28: @@
 This has only to be done once, before the device is plugged in to be used:
 <code bash>
-echo -n 'STM32F1xx ARM Cortex M3 micro-controllers' | sudo tee -a /etc/udev/rules.d/60-st-linkv2.rules
+echo -n 'ST-Link V2 SWJ adapter' | sudo tee -a /etc/udev/rules.d/60-st-linkv2.rules
 echo -n 'ATTR{idVendor}=="0483", ATTR{idProduct}=="3748", MODE="0666"' | sudo tee -a /etc/udev/rules.d/60-st-linkv2.rules
 sudo udevadm control --reload-rules
@@ Line 85: / Line 55: @@
 </code>
-==== Altera USB-Blaster (clone) ====
+I am using cheap clones.
+==== ST-LINK/V2 clone ====
+{{:jtag:mb936_case-front.jpg?0x150|case front}}
+{{:jtag:mb936_case-back.jpg?0x150|case back}}
+{{:jtag:mb936_internal-front.jpg?0x150|internal front}}
+{{:jtag:mb936_internal-front2.jpg?0x150|internal front}}
+{{:jtag:mb936_internal-back.jpg?0x150|internal back}}
+This is a complete rip-off of the [[http://www.st.com/web/catalog/tools/FM146/CL1984/SC724/SS1677/PF251168|ST-LINK/V2]].
+It comes in the same box, with the same cables, the enclosure is the same, even the board name has been taken over (MB936), but the board isn't the same.
+The BOM doesn't match with the [[http://www.st.com/resource/en/bill_of_materials/st-link_v2_bom.zip|original]].\\
+The original adapter come with ESD protection, protection resistors, and a transceiver to allow operating with target signal levels of 1.65V to 5.5V.
+This is completely missing on the clone since the connector pins are directly connected to the micro-controller.
+Thus it only supports target signal levels of 3.3V and sometimes 5V since the pins are 5V tolerant.
+For $9 you can't expect more, and if you want a cheap adapter I recommend the other ones (see below).
+==== ST-LINK V2 aluminium ====
+These adapters come in a small dongle sized aluminium case.
+They supports SWD, and SWIM (for STM8), but not JTAG.
+At $2.5 they are the cheapest clones you can find.\\
+One trick to get this ridiculously low price is to use STM32F101 micro-controllers.
+Compared to the STM32F103 micro-controllers they offer less functionalities, like USB ... yet this is a USB dongle!
+Well this is because these micro-controllers use the same die, but if not all STM32F103 feature tests pass after production they get packages as STM32F101, but it seems that USB still works well enough.
+At least this is my guess.
+It would be interesting to check if the other STM32F103 peripherals normally not present on the STM32F101 work as well, but I wouldn't rely on these.
+After all, they are probably marked as STM32F101 for a good reason.\\
+Similarly the STM32F103C8 is only rated having 64 kB of flash because it didn't pass the flash test, compared to the 128 kB for the STM32F103CB, but they very often have more (you can verify by read/writing and check for errors).
+Several board versions exist and it is hard to know what you will get.
+Always check the pinout on the aluminium case since this also varies.
+=== 2014-06-22 ST-LINK V2 ===
+{{:jtag:alu_dongle_front.jpg?0x100|}}
+{{:jtag:alu_board_front.jpg?0x100|}}
+{{:jtag:alu_board_back.jpg?0x100|}}
+I've also reversed the {{:jtag:alu.pdf|schematic}} for this board.
+One other nice trick they used is to have twos LEDs on the same pin (PA9):
+  * when the pin is set to output high, only one LED lights up
+  * when the pin is set to output low, the other LED light up
+  * when set to input floating, both LEDs are off
+  * when PWM output is used, you can mix the two colors (red and blue) quite well due to the persistence of vision (also because the LEDs are next to each other and the small hole in the case is in the center).
+=== swapped ===
+{{:jtag:reverse-gnd_case-front.jpg?0x100|}}
+{{:jtag:reverse-gnd_internal-front.jpg?0x100|}}
+{{:jtag:reverse-gnd_internal-back.jpg?0x100|}}
+From the outside this looks very similar to the previous one, except that the connector pinout is very different (except for power) and there is only one LED.\\
+No markings are on the board.
+=== 2016-01-18 MX-LINK V2 ===
+{{:jtag:mx-link__case-front.jpg?0x100|}}
+{{:jtag:mx-link__internal-front.jpg?0x100|}}
+{{:jtag:mx-link__internal-back.jpg?0x100|}}
+This one has an "M" logo instead of the ST logo, probably corresponding to the "MX-LINK V2" marking on the board.
+==== Baite ====
+{{:jtag:baite_dongle_front.jpg?0x100|dongle front}}
+{{:jtag:baite_dongle_back.jpg?0x100|dongle back}}
+{{:jtag:baite_board_front.jpg?0x100|board front}}
+{{:jtag:baite_board_back.jpg?0x100|board front}}
+The [[http://betemcu.cn/|Baite]] [[https://www.aliexpress.com/store/product/Best-Quality-ST-Link-stlink-V2-for-STM8S-STM8L-STM32-Cortex-M0-Cortex-M3-SWIM-JTAG/213957_32676015777.html|ST-Link V2]] is my favorite clone since it supports JTAG, SWD, and SWIM (for STM8).
+The seem to use the same board also for several other programmers, and since the pinout is not on the case I've decided to make my own sticker.
+{{:jtag:dsc02406.jpg?0x100|pinout sticker}}
+{{:jtag:st-link_v2_baite.svg?0x100|pinout}}
+I've also reversed the board layout to get the {{:jtag:baite_schematic.pdf|schematic}}.
+The connector pins are all protected with 220 ohms resistors.
+{{:jtag:baite-v2a-board_front.jpg?0x100|board front}}
+{{:jtag:baite-v2a-board_back.jpg?0x100|board front}}
+There is a newer version marked as "V2A" (under the crystal), but the {{:jtag:baite-v2a.pdf|schematic}} is pretty much the small with the following changes:
+  * all pads for the micro-controller are present (there is even solder mask between them)
+  * they added a SWD port
+  * the STM32F103C8 has been replaced with a STM32F101CB, but they are treating it as a STM32F103 (like the other cheap dongles)
+  * the passives are smaller
+  * the routing is horrible
+===== Black Magic Probe =====
+The [[https://github.com/blacksphere/blackmagic/wiki|Black Magic Probe]] (aka. BMP) is a quite nice SWJ adapter because it comes with an embedded GDB server.
+Thus no need to have an OpenOCD server to control the SWJ adapter.
+You can directly connect GDB to this adapter (over USB CDC ACM).\\
+It also comes with a UART port (over a second USB CDC ACM).
+This is very useful while developing (for printf debugging).
+The hardware comes with some disadvantages though:
+  * the ARM Cortex SWJ connector uses a small header (not very dupont-wire friendly)
+  * the separate UART is not always populated (UART is also available on the SWJ connector)
+  * it is quite expensive (> $50)
+  * it is always sold out (and V2.1 on pre-order will take a bit of time until it is available)
+But because the firmware is open source it is possible to port it to other hardware, and [[https://github.com/blacksphere/blackmagic/wiki/Debugger-Hardware|people already did it]].\\
+It has been [[https://medium.com/@paramaggarwal/converting-an-stm32f103-board-to-a-black-magic-probe-c013cf2cc38c|ported]] on the [[stm32f1xx#blue_pill|blue pill]], but I don't find this board as handy as a dongle.\\
+It has also been [[http://blog.linuxbits.io/2016/02/15/cheap-chinese-st-link-v-2-programmer-converted-to-black-magic-probe-debugger/|ported]] to the [[#st-link_v2_aluminium|ST-Link V2 clone]], but then there is no additional UART anymore.\\
+So I decided to port it to the [[#baite|baite]].
+This has less power pins (who needs 2xGND, 2x5V, 3x3.3V anyway), but provides enough function pins to add UART (and SRST).
+To build the firmware ([[https://sourceforge.net/p/blackmagicdebug/mailman/message/35762464/|patch]] integration pending):
+<code bash>
+git clone https://github.com/blacksphere/blackmagic
+cd blackmagic
+git submodule init
+git submodule update
+wget -O 0001-add-new-platform-Baite-ST-Link-V2-clone.patch "https://sourceforge.net/p/blackmagicdebug/mailman/attachment/20170401092652.GA15475%40coil/1/"
+patch -p1 < 0001-add-new-platform-Baite-ST-Link-V2-clone.patch
+make
+cd src
+make clean
+make PROBE_HOST=baite
+</code>
+First we need to re-program the Baite dongle.\\
+As you can see on the {{:jtag:baite_schematic.pdf|schematic}} the JTAG and SWD pins of the micro-controller are not connected (there even are no pads on the board for the pins to be soldered on).
+But on the back of the board you can find test points so to program the device using the serial bootloader:
+^ pin ^ signal ^
+| 1 (square) | RX |
+| 2 | TX |
+| 3 | BOOT0 |
+| 4 | +5V |
+| 5 | GND |
+Use any USB to UART converter and connect the corresponding pins to this port.
+Don't power the Baite dongle over USB since it might then boot the normal application.
+Instead let the USB to UART converter power it.
+To start the serial bootloader when powering the dongle you need to set BOOT0 high by connecting it to +3.3V or DTR (or any high signal present on the USB to UART converter).
+To flash the Black Magic DFU bootloader I used [[https://sourceforge.net/p/stm32flash/wiki/Home/|stm32flash]].
+Since the flash is read/write protected you first need to clear these option bits.
+<code bash>
+# disable flash read protection
+stm32flash -k /dev/ttyUSB0
+# disable flash write protection
+stm32flash -u /dev/ttyUSB0
+# erase flash
+stm32flash -o /dev/ttyUSB0
+# flash DFU bootloader
+stm32flash -w blackmagic/src/blackmagic_dfu.bin /dev/ttyUSB0
+</code>
+Unplug and re-plug the Baite dongle and you should see the device in DFU bootlader mode.
+Flash the main application firmware using dfu-util:
+<code bash>
+dfu-util -d 1d50:6017 -s 0x08002000:leave -D blackmagic.bin
+</code>
+Unplug and re-plug the Baite dongle.
+The adapter should be running the main application and two USB CDC ACM ports will appear.
+You can re-flash the device from the main application using dfu-util:
+<code bash>
+dfu-util -d 1d50:6018 -s 0x08002000:leave -D blackmagic.bin
+</code>
+or short RX to ground (pin 5 and 7) to force the DFU bootloader start when plugin in the dongle (in case the main application is buggy).
+Here is the new "BMP Baite" {{ :jtag:bmp_baite.pdf |pinout}}:
+^ signal ^ pin ^ pin ^ signal ^
+| SRST | 1 | 2| +3.3V |
+| +5V | 3 | 4 | JTCK/SWCLK |
+| RX | 5 (key) | 6 | JTMS/SWDIO |
+| GND | 7 | 8 | JTDO/TRACESWO |
+| TX | 9 | 10 | JTDI |
+**note**: the RX pin is pulled up by a 620 ohms resistor. Thus the TX connected to BMP Baite must by strong enough to drive it low (e.g. not like with the CH340 USB to UART converter).
+If you connect SRST to the target NRST, it is even possible to reset the target board without having to press on the on-board reset button (of there is any):
+<code bash>
+gdb --eval-command="target extended-remote /dev/ttyACM0" --eval-command="monitor hard_srst" --eval-command="quit"
+</code>
+===== Altera USB-Blaster =====
 The [[https://www.buyaltera.com/PartDetail?partId=1212940|USB-Blaster]] is from Altera.
@@ Line 175: / Line 332: @@
 </code>
-==== SEGGER J-Link (clone) ====
+===== SEGGER J-Link =====
 The [[http://www.aliexpress.com/item/FREE-SHIPPING-V8-ARM-Emulator-supports-ARM7-ARM9-ARM11-Cortex-M3-core-ADS-IAR-STM32-Emulator/32262570128.html|O-Link-ARM V8]] is a [[https://www.segger.com/jlink_base.html|SEGGER J-Link]] clone.
@@ Line 186: / Line 343: @@
 That makes it the most complete JTAG adapter I have.
-===== tricks =====
+====== tricks ======
-==== scan chain ====
+===== scan chain =====
 JTAG devices are called Test Access Points (TAP).