> I am not sure how to wire 74HC148 > Can you show how to connect wires 7-20 to 74HC148 and to 11 pins on 7i37 > (00in, 01in, 02in. ………10in)
take a close look at the datasheet http://focus.ti.com/lit/ds/symlink/sn74hc148.pdf the 74hc148 has three output bits, you wire these to your m5i20. since it has three bits it can be in 2^3 or eight (8) different states. So you could potentially wire an 8-way rotary selection switch to the inputs, and it will output a three-bit pattern corresponding to the position of the switch. You would then save 8-3 = 5 I/O pins. With two bits you can have 4 states, so for a 4-position rotary switch you would save 4-2 = 2 I/O pins. if you have lots of I/O pins to spare and are using 3 or 4-way rotary switches it may not be worth it to encode the position of the switch with a 74hc148 Anders ------------------------------------------------------------------------------ Join us December 9, 2009 for the Red Hat Virtual Experience, a free event focused on virtualization and cloud computing. Attend in-depth sessions from your desk. Your couch. Anywhere. http://p.sf.net/sfu/redhat-sfdev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
