I used to use Altera 7xxx EPLD's like glue....put lots of gates, program using JTAG with a programming cable you can build. Really simple to buld from the GUI interface as well. CSB wrote: On Fri, 21 Jul 2006, Gus S Calabrese wrote: > I want to replace a group of 4 74xx simple logic packages with one > device. > What is a popular chip adequate for doing so ? > Well, a GAL would be fine, except for the "programmer" part... you've got either to buy one or make one. But it struck (striked?) me, while I was looking at Xilinx CPLDs : a GAL costs *a lot* more than a small CPLD... Check out the XC9536XL devices: some go for 1.10$ in PLCC-44 package (10ns grade, 3.3V core). The programmer for CPLDs is much simpler as well (JTAG). The only problem I see is the larger package! I personnaly abandon hope for GAL devices... simply too much trouble for what they're worth. Plus, you can't even have seperate reset/ preset signals, you can't play with the clock input (i.e. derive it from a product term), etc. Above all that, you have very few write cycles on a typical GAL, and very few outputs ! Christian VA2CBW -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist --------------------------------- Do you Yahoo!? Next-gen email? Have it all with the all-new Yahoo! Mail Beta. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist