Differences

This shows you the differences between two versions of the page.

--- jtag [2016/02/02 10:00] – add j-link kingkevin
+++ jtag [2017/03/30 12:50] – move 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).
+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.
-===== JTAG adapters =====
+====== SWJ adapters ======
-These are the main JTAG adapters I am using.
+These are the main SWJ adapters I am using.
-==== ST-Link v2 (clone) ====
+===== 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}}
-  * 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 41: / 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 68: / 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).
+==== aluminium ====
+This [[http://www.aliexpress.com/item/Hot-Sale-1PCS-ST-LINK-Stlink-ST-Link-V2-Mini-STM8-STM32-Simulator-Download-Programmer-Programming/32343514985.html|one]] comes in aluminium case.
+It supports SWD, and SWIM (for STM8), but not JTAG.
+They replaced the additional JTAG pins with power pins.
+{{:jtag:dsc02407.jpg?0x100|device front}}
+{{:jtag:dsc02408.jpg?0x100|device back}}
+{{:jtag:dsc02415.jpg?0x100|PCB front}}
+{{:jtag:dsc02410.jpg?0x100|PCB back}}
+STM32F103C8 connection:
+^ STM32F103C8 signal ^ STM32F103C8 pin ^ adapter pin ^ adapter signal ^
+| PB6 | 42 | 1 | RST |
+| PB14 | 27 | 2 | SWDIO |
+| USB GND |  | 3 | GND |
+| USB GND |  | 4 | GND |
+| PB8/PB11 | 45/22 | 5 | SWIM |
+| PA5/PB13 | 15/26 | 6 | SWCLK |
+| LDO VCC |  | 7 | 3.3V |
+| LDO VCC |  | 8 | 3.3V |
+| USB VCC |  | 9 | 5V |
+| USB VCC  |  | 10 | 5V |
+| PA9 | 30 | current source  | LED |
+==== BAITE ====
+The first clone is a [[http://www.aliexpress.com/item/Free-Shipping-1SET-ST-Link-st-link-V2-for-STM8S-STM8L-STM32-Cortex-M0-Cortex-M3/1758613434.html|BAITE]] ST-Link V2.
+It supports JTAG, SWD, and SWIM (for STM8).
+{{: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 connection:
+^ 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 |
+| PA14 | 37 | 6 | JTMS/SWDIO |
+| 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.
+===== Altera USB-Blaster =====
 The [[https://www.buyaltera.com/PartDetail?partId=1212940|USB-Blaster]] is from Altera.
@@ Line 158: / Line 217: @@
 </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 169: / Line 228: @@
 That makes it the most complete JTAG adapter I have.
-===== tricks =====
+====== tricks ======
-==== scan chain ====
+===== scan chain =====
 JTAG devices are called Test Access Points (TAP).