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The CEDT-SW-JTAG Debug Adapter connects your PC's USB port to your ARM based target system board via JTAG or SWD debug interface, and allows you to debug embedded programs running on target hardware.


  • Fast speed USB 2.0 JTAG dongle interface, can be used with all ARM devices for programming and debugging
  • Supports ARM targets working in voltage range 1.8 – 3.3 V DC
  • Uses ARM's standard 2x10 pin JTAG connector and 10 pin SWI connector
  • Adds virtual RS232 port to the computer with all modem signals like: DTR, DSR, DCD, RTS, CTS, Rx, Tx
  • Software supported by OpenOCD
  • Adds virtual 3.3V UART port to the computer with signals Rx, Tx, CTS, RTS
  • Operated on USB bus power

FT2232H configuration

The FT2232h is configured as shown below to work in MPSSE mode to implement the JTAG and SWJTAG Protocol.

  • The lower byte bus of Channel-A is used in MPSSE mode for JTAG implementation
  • The higher byte bus of channel-A is used as GPIO for automatic detection of target supply and Target reset
  • The channel-B is used for UART implementation
  • The SWJTAG is implemented using the lower byte bus of Channel-A along with GPIO.
  • The GPIO's are used for controlling the direction of packet flow i.e., either from target-to-host or host-to-target.

Instructions to use the Debugger

  1. Compile OpenOCD to use with this Adapter
  2. Connect Debugger to PC using USB B-Type connector. The device should be recognized as a USB composite device with USB to serial converter.
  3. Open Device manager and ensure that two COM port devices are detected.
  4. To use the Debugger as USB to RS-232, select the Higher COM port number between the two newly added virtual COM ports.
  5. To use this debugger as interface to target board with OpenOCD replace the interface lines in the Configuration file with the following
interface ft2232
ft2232_device_desc "CEDT-ARM-USB"
ft2232_layout "cedt_arm_jtag"
ft2232_vid_pid 0x0403 0x6010
ft2232_latency 2
jtag_khz 30000