JTAG-lock-pick Tiny 2 is an ARM core processors' JTAG using USB 2.0 bus to connect to PC. The device is based on FTDI FT232H chip – a single channel USB <=> UART/FIFO converter. Designs goals of JTAG-lock-pick Tiny 2 project were to create a small and cheap, but at the same time fully functional and fast, interface that would fit various needs.

Thanks to USB bus the device can be connectedto any PC on the market – it would not be possible with parallel interface (LPT), which is completely obsolete nowadays. Use of more recent standard – USB 2.0 – allows to increase speed of operation by 30 - 270% when compared to USB 1.x.

Maximum frequency of JTAG interface's clock is 30MHz and it is also possible to use RTCK mode (so called Adaptive Clocking, in which clock frequency adapts itself dynamically to target chip's clock, using feedback connection). Use of advanced CPLD chip – Lattice's ispMACH 4000ZE series – as line buffers allows connecting target devices with wide range of supply voltage – from 1.4V to 3.6V. Inputs of the interface tolerate voltage higher than supply voltage (up to 5.5V), so it's possible to use 5V target chips under additional conditions (more information in manual).

Additionally JTAG-lock-pick Tiny 2 supports communication with target chip via new SWD (Serial Wire Debug) interface, which uses only two lines – bidirectional data line SWDIO and clock SWCLK.

JTAG-lock-pick Tiny 2 interface can be used to program other types of target chips, such as FPGA, CPLD, AVR or MIPS.

JTAG-lock-pick Tiny 2 is partially compatible with KT-LINK interface manufactured by KrisTech, thus in many applications it is possible to use existing configurations instead of creating them manually.

JTAG-lock-pick Tiny 2 interface has separate SRST and TRST lines, which can be independently configured to push-pull or open-drain mode.

JTAG-lock-pick Tiny 2 project is an improved and miniaturized successor to JTAG-lock-pick 1.x.x.

Supported target chips

JTAG-lock-pick Tiny 2 interface and PC software that uses it (among others: OpenOCD, Atollic TrueSTUDIO, CooCox CoIDE, Keil MDK-ARM, IAR Embedded Workbench for ARM, Rowley CrossWorks for ARM, more information in manual) are able to communicate with almost any existing type of ARM processor, including the most popular:

Cortex-M3 (STM32, LM3S, LPC17xx, AT91SAM3, …),
ARM7 (LPC2xxx, AT91SAM7, STR7xx, ...),
ARM9 (LPC3xxx, AT91SAM9, STR9xx, ...),
...

Additionally this interface can be used to program other types of target chips, such as FPGA, CPLD, AVR or MIPS.

The only limiting factor is support for specific chip in PC software.

“Strong points” of JTAG-lock-pick Tiny 2 project

USB 2.0 Hi-Speed 480Mbps bus,
support for SWD (Serial Wire Debug) interface,
JTAG clock frequency up to 30MHz, support for Adaptive Clocking using RTCK line,
safe and reliable communication with target devices with supply voltage in the range from 1.4V up to 3.6V, inputs tolerate up to 5.5V signals, all lines buffered with advanced CPLD chip,
separate SRST and TRST lines, which can be independently configured to push-pull or open-drain mode,
transparent heat-shrink tube “enclosure”, which protects JTAG, connected PC and target device from accidental damage,
small size of whole device (approximate dimensions 55mm x 34mm x 12mm) and small price,
...

Contents of the package

JTAG-lock-pick Tiny 2 debugger / programmer, machine assembled, tested, enclosed in transparent heat-shrink tube (approximate dimensions 55mm x 34mm x 12mm),
JTAG <=> target ribbon cable, 20cm,
USB mini-B cable, black, 1,8m,
DVD with manual, drivers, set of useful software – free (gcc toolchains: CodeSourcery, Linaro and bleeding-edge-toolchain; IDE Eclipse, OpenOCD, CooCox CoIDE) and proprietary in evaluation versions (Atollic TrueSTUDIO for STM32 Lite, Keil MDK-ARM + CooCox CoMDKPlugin, IAR Embedded Workbench for ARM + CooCox CoIARPlugin, Rowley CrossWorks for ARM) – all of them in the most recent versions – and other required files.

On our website in Download > JTAG-lock-pick section you can find several files related to this project: manual (with schematic diagram of circuit, schematic diagram of CPLD and bill of materials) and drivers (WinUSB, libusb-win32 and ftd2xx).