Talk:Serial adapters

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Revision as of 01:44, 24 August 2012 by Peasthope (Talk | contribs)
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Open Firmware

The section entitled "Open Firmware" refers to two XOs with serial ports connected directly? Serial adapters are not used? Wouldn't hurt to mention this. The crossover cable requires two J1 CN24 female connectors and a cable with at least 3 conductors. Connectors available from retail vendors are mentioned in the later section "XO Serial Ports - physical interface". Regards, Peasthope 18:05, 18 August 2012 (UTC)

Thanks. Yes, USB serial adapters are not needed, and won't help, in the XO to XO configuration, but this is not Open Firmware specific, the same can be done with Linux. No, a crossover cable does not require two connectors, it could be fabricated in several ways, depending on what is available. J1 and CN24 are a model-specific identifier, so I would not mention them in the context of software. --Quozl 23:05, 20 August 2012 (UTC)

> No, a crossover cable does not require two connectors, ...

Do you visualize soldering wires directly to the UART? I'd rather make a crossover cable with a connector on each end to plug into Jn on the board; whatever n is for the model in question.

> J1 and CN24 are a model-specific identifier, so I would not mention them in the context of software.

Agreed but a crossover cable is hardware and the software won't work without it and the present description is better but still unclear. What about discussing the crossover connection under "Connecting up" rather than under "Open Firmware".

> ... the same can be done with Linux.

Typically using an RS232 crossover cable to connect serial ports on two machines. A serial connection directly to a system board would be somewhat unusual. Possible but you'd want to be sure about voltage levels. When connectors are available, as on the XO, they should be used.

> [table] A crossover cable consists of the following:
> host pin (cable colour) target pin (cable colour) purpose
> GND (orange) ...

Where do you see these colors? Not on the system board. On the serial adapter? But the premise is that we are not using serial adapters. Shouldn't the table refer to something visible such as conductor numbers in http://wiki.laptop.org/go/File:Closeup-J1.png? Regards, ... Peasthope 01:44, 24 August 2012 (UTC)

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