Marcos, -----Mensaje original----- De: Marcos Sassahara Para: PICLIST@MITVMA.MIT.EDU Fecha: viernes, 28 de enero de 2000 13:07 Asunto: Re: First PIC project... |Friends, | |First of all I want to apologize for sendind comments in the middle of your |discussion. I am a hobbyst and know how terrible is to create a good PCB |lay-out on a PC tool like tango for example and don't be able to end the |process in a more professional way, I mean, have a good artwork but have to |make the board manually. Won't be fastastic if you could print the lay out |(using a common deskjet printer) over a kind of paper able to transfer the |drawing directly to the board? No UV or any other method involving light or |Chemistry or silk screen? For a quick prototyping: Have you tried with "Press & Peel" paper ? You print (with Laser printer) on this paper and then you can transfer the design to the board by heating. It's not cheap, but useful for a good prototype. |The 4017 is a sequencial counter of 10 outputs. The first three outputs can |be used to drive three displays. The pic will RESET the |4017 to make the first display active. A pulse in the CLOCK pin will change |the output to the second display and a new pulse to the third. |To set the initial time, one push button can select the display to be |configured and other one can increase the number displayed. One start |counter should be present. The necessary PIC ports will be: | |7 - displays segments |1 - 4017 reset |1 - 4017 clock |1 - Increase push button |1 - Select display push button |1 - Start Counting / Config mode switch push button |1 - Load | |Counter will display 99.5 (99min 50sec) to 00.0 in steps of 10sec. A little bit more efficient: You can elliminate the 4017 multiplexing the displays by soft. Now, the pins: 7 - displays segments 1 - Base of 1st. transistor (driving the 1st display). 1 - Base of 2nd. transistor. 1 - Base of 3rd. transistor. 1 - Config mode switch push button/In Config mode: Select display. 1 - Start Counting/In Config mode: Increase push button 1 - Load (Going off the Config mode by time) |Regards. Regards, S.-