1
\$\begingroup\$

For the mbed LPC 1768, I am trying to establish a USB connection with an external device (pins 31, 32, and 39 for D+, D-, and Vbus, respectively). According to USB in a NutShell: Connectors, a 15kΩ resistor must be connected to D+ and D-. Are these resistors included within the mbed, or will they have to be connected externally?

\$\endgroup\$

2 Answers 2

2
\$\begingroup\$

The LPC1768 USB controller is capable of acting as host, device, or even dynamically switching (On-The-Go). Since these resistors need to be on the host side only, it wouldn't make sense to include them on a development kit (if you did, you lose the ability to act as a USB device).

\$\endgroup\$
0
3
\$\begingroup\$

You'll have to add them yourself; the mbed LPC1768 schematic doesn't show them on-board.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.