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On Saturday 05 Nov 2011 09:20:19 Kfir Lavi wrote: |
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> Hi all, |
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> I have a problem connecting my laptop to my server at home with a serial |
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> cable. |
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> I have cable end for /dev/ttyS0 and 2 cable ends for /dev/ttyUSB0. |
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> This lets me test the connection between all serial outputs. |
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> Desktop1-minicom <-> Desktop2-minicom |
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> works with all connections, i.e ttyUSB0 <-> ttyUSB0, or ttyS0 <-> ttyUSB0 |
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> and viseversa. |
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> So when connecting 2 desktop computers everything works as expected. |
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> |
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> The problem: |
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> When I connect my laptop to any of those desktops, I get just one way |
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> connection! |
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> If I swap the sides of the cable, the one way connection switch side. |
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> The laptop doesn't have ttyS0, so it have to be connected via ttyUSB0 |
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> When I swap sides, it is just between two usb dongles. |
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> |
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> The usb dongles are PL2303 both sides. |
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> Settings of minicom is 38400 8n1 Hardware Flow Control=OFF |
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> |
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> Laptop setserial: |
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> setserial -a /dev/ttyUSB0 |
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> /dev/ttyUSB0, Line 0, UART: 16654, Port: 0x0000, IRQ: 0 |
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> Baud_base: 460800, close_delay: 0, divisor: 0 |
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> closing_wait: infinte |
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> Flags: spd_normal |
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> |
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> Desktop1 setserial: |
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> setserial -a /dev/ttyS0 |
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> /dev/ttyS0, Line 0, UART: 16550A, Port: 0x03f8, IRQ: 4 |
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> Baud_base: 115200, close_delay: 50, divisor: 0 |
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> closing_wait: 3000 |
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> Flags: spd_normal skip_test |
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> |
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> setserial -a /dev/ttyUSB0 |
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> /dev/ttyUSB0, Line 0, UART: 16654, Port: 0x0000, IRQ: 0 |
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> Baud_base: 460800, close_delay: 0, divisor: 0 |
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> closing_wait: infinte |
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> Flags: spd_normal |
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> |
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> I tried to add the skip_test but this seems to be not working. |
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> I'm not sure what to do next. |
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> |
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> Any help will be appreciated, |
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> Thanks, |
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> Kfir |
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|
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I think that you will need the pin mapping of a 'null modem' to be able to |
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have bidirectional connectivity. |
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|
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Have a look here: |
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|
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http://en.wikipedia.org/wiki/Null_modem |
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|
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I think I still have an RS-232 to D9 null modem adaptor somewhere in my bins |
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of spares. |
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|
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HTH. |
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-- |
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Regards, |
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Mick |
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