Some time ago someone on this list posted a question regarding troublesome connections between modem and Duo. I found a possible cause in a Macintosh Technical Note : <http://www.archaic-apples.com/mac/hardware/HW28-PowerBook%20Miscellanea.pdf> <quote> It Feels Like I’m Floating You may have problems connecting RS-232 from PowerBook to PowerBook or from PowerBook to other battery-powered device if your connection is not properly grounded. This will result in unacceptable noise in your signal or a complete failure in the two devices to interpret the transmitted voltage levels correctly. Serial communications using RS-232 voltage levels depend on reference to ground. Because the PowerBooks are freestanding battery-powered devices, they are properly grounded with respect to RS-232 only when the cable converting their RS-422 to RS-232 also connects to a proper signal ground and shield ground. (RS-422 uses balanced-pair signals and does not have this problem.) This is a common cause of your program getting stuck in the vSyncWait routine as the serial driver is waiting for character transmission to complete while the SCC waits for an appropriate DTR or CTS that can’t be seen due to a lack of proper ground reference. To remedy this problem, you will need to make sure the cable you are using connects the signal and shield grounds to both devices and that at some point these grounds are connected to an actual grounding source (grounding strap, ground plug, or similar “metal pipe into the planet”). Plugging in the wall power adapter will have no effect on this problem—it provides no grounding to the PowerBook. </quote> HTH Luc _________________________________________________ Je eigen e-mail, fax en voice mail: alles in een! Nu bij Clickx! op http://www.clickx.be/mstation. ---------- Duo/2400 List, The friendliest place on the Net! A listserv for users and fans of Mac subportables. FAQ at <http://www.themacintoshguy.com/lists/DuoListFAQ.shtml> Be sure to visit Mac2400! <http://www.sineware.com/mac2400> To unsubscribe, E-mail to: <[EMAIL PROTECTED]> To switch to the DIGEST mode, E-mail to <[EMAIL PROTECTED]> Need help from a real person? Try. <[EMAIL PROTECTED]> ---------- Dr. Bott | 10/100 Ethernet for your 2400 is finally here! MPC-100 | <http://www.drbott.com/prod/mpc100.html> NineWire | If they are cool enough to host this list... Digital Solutions | ...you should check them out! http://www.NineWire.com/ Midwest Mac Parts ][ <http://www.midwestmac.com> After-market parts for Macs. ][ 888-356-1104 ][ MacResQ Specials: LaCie SCSI CDR From $99! PowerBook 3400/200 Only $879! Norton AntiVirus 6 Only $19! We Stock PARTS! <http://www.macresq.com>
