Help with USB01A


I’m using a Pololu Serial-to-USB converter USB01A, connected on a PIC16F876. It’s works fine at 9600 bds, but I would to use it at 19200 bds. I can easily modify the PIC baudrate, but USB01A seems to be configured at 9600 bds.
How can I modify this configuration?
Thanks for all,

Hello, Gerard.

There is a USB command for changing the baud rate of the USB-to-Serial Adapter and most terminal programs will present the baud rate as an option that you can select before or after connecting to COM port. If you told me what operating system you are using and what kind of software you are running to communicate with the serial adapter, I might be able to give more specific advice on how to set the baud rate.


Hi David,

Thanks for your help. I’m waiting this USB command to set the baudrate. On one side, my USB-to-serial adapter USB01A is connected with a PIC16F876. On the other, there is actually a MacBookPro running Snow Leopard system.
But, if it’s not possible to set the baudrate via the MacBook, I can use a Windows PC to modify the configuration of the USB01A.

Thanks for all

What kind of software you are running to communicate with the serial adapter?


No dedicated software. Just the standard “terminal” program of MacOsX, witch launch a Linuxlike shell in a window.

Here is my commands (in su mode):
kextload /System/Library/Extensions/SiLabsUSBDriver.kext
screen /dev/tty.SLAB_USBtoUART


I can also use Hyper-terminal on a Window pc.

In this case, screen is the program you are using to talk to the serial port and you should be able to specify the baud rate by supplying an extra argument. Please try:

screen /dev/tty.SLAB_USBtoUART 19200


Hi David,
It seems to be good.
Thanks a lot