> > With those charge pumps, it is probably as EMC unfriendly as their MAX232 > devices that don't need charge pumps (cannot remember their exact part > number). I used the 3110s once. It's all that and more. If I need multiple serial ports again, I'm going to use AVRs for them. Those charge pumps are not all that nice, and I'd far rather have a single switcher than eight charge pumps banging away. -- > Feel the power of the dark side! Atmel AVR -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist