ok, now i reply. Your answer did not help me, pardon me. this is not basic question at all, because i can run at all serial ports on standard linux on PC , but not on the Assabet nor the mediaEngine. now i tried a simple test: on inittab - T0:12345:respawn:/sbin/getty -L ttyS1 9600 vt100 instead of ttyS0 (running 2.4.2 kernel, old tty's)
but no login prompt at all on S1 ! (also tried with 2.4.17 kernel with new ttys -> the same .) i measured the voltage on both ports on the mediaEngine and its the same - -8v between pins 3 and 5. what is wrong ? my final goal is simply use minicom on the mediaEngine, so i can monitor a telephony equipment cage thru the mediaEngine. besides: how can i reach this goal with ttyS0 ? i failed this also , i cannot see nothing on the arm-minicom i built. did i missed something ? (terminfo, stty, ?) what is the difference between old and new ttys ? Gad ----- Original Message ----- From: "Russell King - ARM Linux" <[EMAIL PROTECTED]> To: "Gad Hayisraeli" <[EMAIL PROTECTED]> Cc: "Linux-Arm-kernel List" <[EMAIL PROTECTED]> Sent: Sunday, January 27, 2002 9:29 PM Subject: Re: serial connection with sa1110 - no response > On Sun, Jan 27, 2002 at 07:42:14PM +0200, Gad Hayisraeli wrote: > > i have a mediaEngine board from BSE, sa1110 based, with 2 serial ports - > > /dev/ttySA0, SA1 > > ( i use 2.4.17 kernel with appr. patches ) > > i can use the SA0 to see debug info of the kerenl , to login thru it and its > > fine. > > but when i try to use minicom on this card, compiled to arm, i cannot see > > anything on the minicom screen. > > i investigated alot and discovered the the comm. device i'm trying to > > connect to is a DTE (voltage on pin 2, zero on 3, ground on 5) and my arm > > card is a DCE (voltage on pin 3, zero on 2, ground on 5) > > when i tried to connect them in crossing metod (2 to 3 , 3 to 2) i did not > > see anything, and neither in the straight way (2 to 2 , 3 to 3). offcourse > > pin 5 to 5 always connected. > > the connection between arm card and the PC is good,and also from the device > > to the PC. > > This is basic RS232 type stuff and isn't related to ARM nor Linux at all. > > If you're connecting a DTE to a DCE, pins 2, 3, and 5 must be connected > straight through. > > If you're connecting DCE to DCE, you need to swap pins 2 and 3 (ie, NULL > modem cable). > > If you're only using pins 2, 3 and 5, you must disable all hardware flow > control. > > _______________________________________________ > http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm-kernel > Please visit the above address for information on this list. _______________________________________________ http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm Please visit the above address for information on this list.
