Folks, Good information, but while the "ANSI/EIA/TIA-723 Alt B." standard does specify the DE-9 connector, please keep in mind that the converse is NOT true.
Having a DE-9 connector does NOT infer that it is an RS-232 connector, or even a serial connector. The connector on the K2 is clearly labeled "AUX I/O" and that labeling indicates that it has Auxiliary Input and Output lines - which should be an indication connecting to that point that the manual must be consulted to determine the pinout and signal usage - this is true for ANY similar connector, even the DB-25 (which is also used in the PC as a parallel port. If the connector conformed to any standard, be that RS-232 or ANSI/EIA/TIA-723 Alt B, or any other, it would likely be proudly labeled as such rather than "AUX I/O". Even the early IBM PCs (which were one of the first users of the DE-9 for a serial port) did not call them RS-232 ports, they were referred to simply as serial ports, specifically because they did not comply with the RS-232C standard (which was the current level at that time). They did use similar line names, but electrically and physically, those PC serial ports did not comply completely with the standard - but they did work with RS-232 level signals in most cases, while in other cases they caused headaches, particularly with longer line lengths, but I digress. Protect your K2 - the signals from the K2 should not hurt a proper RS-232 level receiver (in your computer), but applying the RS-232 switching voltages to your K2 will likely cause the rapid demise of the devices connected to the AUXBUS line inside your K2 and perhaps other fatalities can result too. Use the Elecraft specified pinout and purpose for any cable ocnnected to the K2 AUX I/O. 73, Don W3FPR > -----Original Message----- > RS-232 and it's successors are interface standards, and as such > define electrical signal, logical function and physical > connection standards. In fact, the one thing it doesn't define is > an upper layer signaling protocol - which is why you must also > know whether you're dealing with sync/async and the specific > serial encoding to be used. It predates the modern ISO layered > architecture, but would fit best as a Physical Layer (Layer 1) standard. > > RS-232 has always specified a cable pinout; originally on an > unspecified 25 pin connector. Later, in RS-232C, it specified the > common Cannon DB-25 connector. > > RS-232 as such is obsolete, and in informal use is normally taken > to refer to the current standard, ANSI/EIA/TIA-723-1998 "High > Speed 232 Type DTE/DCE Interface," which replaced EIA/TIA-232. > The standard says the DE-9 interface shall be referred to as > "ANSI/EIA/TIA-723 Alt B." In addition to the regular DB-25, there > is also a 26 pin "Alt A." > > _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
