Integrating XTAG2 into a PCB

[rp181]

I am designing a system using the L2 processor. I would like USB connectivity, for programming and data transfer. I need all the IO on the L2, so I will be using another L1 to handle the USB.

If I copy the XTAG2 schematic (allowed in license), what kind of software do I need to load onto the L1. the MODE pins are configured to boot from SPI, am I right in thinking that this is basically booting from USB?

Is the XTAG code available anywhere?

[Andy]

Hi rp181,

You'll need to program the OTP with the USB bootloader. All the code you need is available on Github here:

https://github.com/xcore/proj_xtag2

[rp181]

Ok. Will there be a problem programming it while the output is connected to the L2 device, or do I need to program it before connecting?

Also, the XTAG has a component called FB1 in series with the VBUS line on the USB connector. What is this? the schematic says its rated 1700ma and 330R.

Do I need to connect VBUS? I plan on having external 5v.

[leon_heller]

FB indicates a ferrite bead.