Floss-JTAG
Floss-JTAG is a small Open Hardware USB JTAG adapter for 3.3V targets, designed by Piotr Esden-Tempski.
Schematics and PCB layouts are licensed under the CC-BY-SA 3.0 license.
Downloads
The latest schematics, PCB layouts, are available from GitHub:
$ git clone git://github.com/esden/floss-jtag.git
Design
- Floss-JTAG is a tiny board (34.5mm x 17mm) with mini USB and Molex picoblade(TM) connectors.
- It uses the FT2232H USB-to-serial chip.
- The original target is Open-BLDC and Openmulticopter but it can also be used for all other 3.3V targets.
Software used
- The board was designed with Eagle PCB software (for commercial use of the Floss-JTAG design a commercial license of Eagle has to be purchased).
- OpenOCD includes the necessary configuration file (flossjtag.cfg and flossjtag-noeeprom.cfg) and support to use Floss-JTAG for programming and debugging targets.
Further resources
- More information is available from the Floss-JTAG V0.1 Assembly and V0.2 boards blog post.
- There's an identi.ca group for the project.
- The OpenPilot project (new page here) has created a modified version of the Floss-JTAG hardware (which is now in the main repo).
Parts list
| Quantity | Device | Footprint | Value | Refdes | Comments |
|---|---|---|---|---|---|
| 1 | FT2232HL | LQFP64 | — | IC1 | — |
| 1 | 1117 V-Reg | SOT223 | 3.3V | IC2 | — |
| 1 | Molex Picoblade 8Pin | 53261-08 | — | JTAG | — |
| 1 | Molex Picoblade 4Pin | 53261-04 | — | X2 | — |
| 1 | Micro USB Conn | UX60A-MB-5ST | — | X3 | — |
| 1 | Quarz | NX3225SA | 12MHz | X3 | — |
| 1 | Green LED | 0603 | Green | LED1 | — |
| 1 | Red LED | 0603 | Red | LED2 | — |
| 11 | Ceramic Capacitor | 0603 | 100nF | C1, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12 | — |
| 2 | Ceramic Capacitor | 0603 | 27pF | C15, C16 | — |
| 1 | Tantal Capacitor | 3216/A | 3.3uF | C2 | — |
| 2 | Tantal Capacitor | 3216/A | 4.7uF | C13, C14 | — |
| 1 | Resistor | 0603 | 1k | R1 | — |
| 1 | Resistor | 0603 | 12k | R2 | — |
| 2 | Resistor | 0603 | 220 | R3, R4 | — |
| 2 | Ferrite Bead | 0603 | 600Ohm 500mA | L1, L2 | — |
Where to buy
The hardware is now also available for purchase from the Joby Robotics shop:
- FLOSS-JTAG with Lisa/L UART Cable
- FLOSS JTAG with Lisa/M UART Cable
- Lisa/L to FLOSS-JTAG UART Cable
- Lisa/M to FLOSS JTAG UART Cable
- Cortex JTAG cable
