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howto:serial_level_adapter 2010/08/01 19:17 howto:serial_level_adapter 2017/09/06 18:38 current
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 +====== Note ======
 +
 +These directions will only be helpful if your PC has an old-school serial port, and even then it's a lot of work. It's far easier to purchase a [[http://www.ftdichip.com/Products/Cables/USBTTLSerial.htm|USB to +3.3V level shifter]] to get the job done.
 +
====== Building your own level converter ====== ====== Building your own level converter ======
To adapt 3.3 TTL logic from NAS to +15/-15 PC serial, you can build your own converter. To adapt 3.3 TTL logic from NAS to +15/-15 PC serial, you can build your own converter.
-This is the schema I used, from [[http://sodoityourself.com/max232-serial-level-converter|Sodoityourself]] with a two errors corrected and explicit pinout for DB-9 female.+This schema is from [[http://sodoityourself.com/max232-serial-level-converter|Sodoityourself]] with two errors corrected and explicit pinout for DB-9 female. 
 + 
 +{{howto:max_232_level_converter2.png|}}
-{{howto:max_232_level_converter.png|}}+Please note that MAX232 circuit can't use 3.3 Vcc from serial Vcc, you must pick up 5V elsewhere (on board or from external power supply), or else use a MAX3223, that accepts 3.3V power supply. 
 +The original schema came with Rx and Tx swapped one with each other, have a look to your level converter's datasheet if any doubt.
-Please note that MAX232 circuit cann't use 3.3 Vcc from serial Vcc, you must pick up 5V elsewhere (on board or from external power supply), or else use another level converter. +This schema is easy to apply on a evaluation board.
-The original schema came with Rx and Tx swapped one with each other, have a look to RS-232 datasheet if any doubt.+
-This schema is easy to apply on a evaluation board, so did I.+{{howto:quick_and_dirty_serial_lvl_adapter.jpg|}}

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