Serial Driver and RS485 problem (Debian Etch/ 2.6.18-6)
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The machine is a Mini PC with 4 serial port:
-ttyS0
-ttyS1
-ttyS2
for RS232 connection
and
-ttyS3
for RS232 / RS485 Connection (Selection is done by internal jumpers that enable a SP485EC chip)
on Debian I can use port ttyS0 and ttyS1 (RS232) without problem. ttyS2 is not on the rear panel (I don't know where it is...) so I can't use it. The last port, ttyS3, is recognized by the OS but I can't send or receive anything neither via RS485 nor via RS232.
On a Windows OS I can the fourth port ttyS3 (COM4) via RS485 and RS485.
I'm very confused: I tried a lot of software like GtkTerm, CuteCom, Minicom, scope.... but nothing!
from dmsg:
[...]
Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing enabled
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
serial8250: ttyS2 at I/O 0x3e8 (irq = 4) is a 16550A
serial8250: ttyS3 at I/O 0x2e8 (irq = 3) is a 16550A
00:07: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:08: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
00:09: ttyS2 at I/O 0x3e8 (irq = 10) is a 16550A
00:0a: ttyS3 at I/O 0x2e8 (irq = 11) is a 16550A
[...]
Any suggest would be very appreciated!
Best regards,
Giacomo Pennella
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