In a message dated 4/17/2007 10:28:31 Pacific Daylight Time, [EMAIL PROTECTED] writes:
What are some examples of > RS-232 hosts that need to talk to GPIB test equipment? Old/retired laptops > being used as dumb terminals? Legacy DOS apps that don't have any form of > USB support? Both? > > -- john, KE5FX Hi John, in our case (Jackson-Labs FireFox Signal Generator) we use the Signal Generators' internal RS-232 port to drive a GPIP HP power meter such as the 436 etc to do an automatic RF level calibration of the generator. The Signal Generator becomes a GPIB host via it's RS232 port and a modified version of the Abdul board and controls the RF Power meter (setting frequency, and other parameters in the meter, and reading the RF power from the meter). Later models of the Agilent power meter such as the E4418 series have a built in RS-232 port and can connect directly to our FireFox generator - a simple null-modem cable does the trick. These power meters don't have USB ports, and if they did, we would have to have a USB host on our generator - a nightmare scenario for our software. So we get the best of all three worlds: * We ship a commercial RS-232 to USB adaptor with our generator for users who don't have RS-232 ports on their PC's anymore, so USB is fully supported and it adds less than $20 to the production cost of the generator to support both USB and RS-232. * We can drive the newer Agilent power meters directly if they have RS-232 ports (E4418 etc) * We can drive the older Agilent GPIB-only power meters such as the 436 using a modified version of the Abdul USB to GPIB board which was modified to have a true RS-232 connector. By the way: the biggest drawback of a USB port on an embedded system in my opinion is that users expect to be able to plug-in any type of device (USB HDD, USB Memory Stick, USB Printers etc) and have them work magically. That doesen't even work properly on Windows sometimes. bye, Said ************************************** See what's free at http://www.aol.com. _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
