MOD-RS485-ISO and A20

[luimarma]

Hello all,

I am writing a program with an Olinuxino A20 that has to send and receive messages to a rs-485 device in half duplex.
For this I have made use of the MOD-RS485-ISO in UEXT2
After openning ttyS2 in raw mode I know that I have to set register 0x30 of address 0x22 to 0x01 to send data and to 0x02 to receive data. My problem is that I always get some garbage every time that I set the MOD-RS485-ISO to enable read mode.
To make sure that this was not my fault I made a test using minicom in one terminal and i2cset in the another terminal:
"Enable send"
root@a20-olimex:~# i2cset -y -f 1 0x22 0x30 0x01
"Enable receive"
root@a20-olimex:~# i2cset -y -f 1 0x22 0x30 0x02

Every time I repeat the set of commands I can see a garbage character on the minicom terminal.

Is this a MOD-RS485-ISO firmware problem?
Any Idea how to solve this?

Thanks in advance,

Luis