PORTS Forum

Ports and Interfaces => Serial Ports => Topic started by: onnimikki on November 23, 2011, 06:00:06 am

Title: RS485: 75176A vs. 75176B
Post by: onnimikki on November 23, 2011, 06:00:06 am

Hi,

I've received a microcontroller board which is supposed to be capable of RS485, but the driver is a TI 75176A.  According to the datasheet (http://www.ti.com/lit/ds/symlink/sn75176a.pdf) it's a RS422 driver.  The "B" version (http://www.ti.com/lit/ds/symlink/sn75176b.pdf) of this driver is said to be 422 and 485.  However, scanning both datasheets I can't seem to find any real difference between them.  Does anyone know if the "A" version will work with a RS485 device?

Thanks,

James

Title: Re: RS485: 75176A vs. 75176B
Post by: Jan Axelson on November 23, 2011, 03:55:31 pm

RS-422 supports up to 10 receivers.

RS-485 supports up to 32 unit loads. RS-485 receivers are typically <= 1 unit load.

Jan