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???
02/05/07 18:11
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 		 #132067 - CMOS?
Given the parts that I have on hand, it seems that I could use CMOS gates in my 8051 system/programmer combo.

BUT, from what I think I know, CMOS is slower, and requires resistors for floating inputs.

Since I am working with the 80C51BH and since I am using 18.432Mhz crystal, I want to know if the CMOS logic gates can process the PSEN signal?

At the moment, I am using 74HC and 74HCT series chips because I'm afraid CMOS won't work.

Let me ask this another way. What is the fastest oscillator speed a 4000 series cmos chip can detect and process?

List of 45 messages in thread
TopicAuthorDate
CMOS?            01/01/70 00:00      
   74HC and 74HCT IS CMOS!            01/01/70 00:00      
      yes            01/01/70 00:00      
         a datasheet and a calculator            01/01/70 00:00      
   Why do you want to "process the PSEN signal" I kno            01/01/70 00:00      
      You need to stick your nose in the books, Mike            01/01/70 00:00      
         umm.            01/01/70 00:00      
            WHAT are you doing with the PSEN ?            01/01/70 00:00      
               programmer + system            01/01/70 00:00      
                  80C51BH doesn't have EPROM            01/01/70 00:00      
                     He's using it as an 80C31            01/01/70 00:00      
                     im meant            01/01/70 00:00      
                  Ambiguous            01/01/70 00:00      
                     LPT            01/01/70 00:00      
                        Is it T0 and T1, or T1 and T2?            01/01/70 00:00      
                           T0 and T1 and, for a '52 T2            01/01/70 00:00      
            What do you mean \"ummm\"            01/01/70 00:00      
               welcome to "Trying"            01/01/70 00:00      
                  nobody thinks you're stupid, however ...            01/01/70 00:00      
                     answer.            01/01/70 00:00      
                        why screw with the clock?            01/01/70 00:00      
                           stop trying to make deals!            01/01/70 00:00      
                              not necessarily            01/01/70 00:00      
                                 ok            01/01/70 00:00      
                                    sorry, I goofed            01/01/70 00:00      
                              Because...            01/01/70 00:00      
                                 Yes, but will it work? It's ATMEL ... (yechhh!)            01/01/70 00:00      
                                 Just to play it safe            01/01/70 00:00      
                                    or try the Maxim/DALLAS parts ...            01/01/70 00:00      
                                       BINGO            01/01/70 00:00      
                                       Not a good first chip            01/01/70 00:00      
                                          What's his primary purpose            01/01/70 00:00      
                                       Mike - FREE CHIP            01/01/70 00:00      
                        An easier way?            01/01/70 00:00      
                           if he is to get another chip, then            01/01/70 00:00      
                              Harder than it needs to be            01/01/70 00:00      
                                 Let him do what he wants! He'll learn something.            01/01/70 00:00      
                                    a small correction            01/01/70 00:00      
                                       Well, I wouldn't know ... I don't use ATMEL            01/01/70 00:00      
                                    answers....            01/01/70 00:00      
                                       TOTALLY and ABSOLUTELY incorrect. if "the flash            01/01/70 00:00      
                                          .            01/01/70 00:00      
                                             Mike ,,, there are other problems ...            01/01/70 00:00      
                        There may be some surprises ...            01/01/70 00:00      
               two Timers            01/01/70 00:00      

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