On Wed, 10 Feb 2010, Paul Keeton wrote: > Date: Wed, 10 Feb 2010 19:46:21 -0500 > From: Paul Keeton <[email protected]> > Reply-To: "Enhanced Machine Controller (EMC)" > <[email protected]> > To: EMC Users Group <[email protected]> > Subject: [Emc-users] Hostmot question > > Hello, > > I am using a mesa 5i20 for general purpose I/O. All pins are > gpio. This is what I am doing..... > > setp hm2_5i20.0.gpio.000.is_output 1 > net classicladder.0.out-00 => hm2_5i20.0.gpio.000.out > > When classicladder.0.out-00 is on hal config shows that > hm2_5i20.0.gpio.000.out is also on but I get no output out of the opto22 > module. The led on the opto board doesn't light up either. If I check an > input with the same cable on a different opto board through a different 5i20 > port it works fine and shows in hal config also. Any clue on what is causing > this? I want to use 48 I/O pins with 24 inputs on one opto board and 24 outs > on the other. In other words my ins are working but my outs are not. > > Thanks, > Paul
Note that OPTO22 racks are "active low" so a low GPIO output turns the SSR on and a high output turns the SSR off. This is because OPTO22 SSRs have their input + pins all tied to the +5 pin on pin 49 of the interface cable. This is why open drain mode is suggested to guarantee the the LEDs in the SSRs are fully off when the FPGA output pins are high. The default push-pull output mode only swings up to 3.3V, which means the SSRs will still see 1.7V when they are supposed to be off, leading to flakey behavior. So in addition to is_opendrain, because the outputs are active low, you most likely want the invert_output parameter set as well for GPIO pins driving OPTO22 racks. Also if outputs dont work, make sure the flat cable pin 49 5V power from the 5I20 is getting to the OPTO22 rack. Some racks have power option jumpers, and the rack need to be jumpered to its 5V supply comes from the flat cable. Peter Wallace Mesa Electronics ------------------------------------------------------------------------------ SOLARIS 10 is the OS for Data Centers - provides features such as DTrace, Predictive Self Healing and Award Winning ZFS. Get Solaris 10 NOW http://p.sf.net/sfu/solaris-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
