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???
02/05/07 13:26
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 		 #132028 - I explain
Responding to: ???'s previous message
I haven't made it to the etching stage. I failed at the developing stage. And how can overexposure make the board fail?

My pads are 1.2mm in diameter (circles) with 0.65mm holes for drilling.

The big problem is optimal arrangement, especially arranging an 8K RAM (CY7C-185), and a 32K EEPROM (atmel AT28C256) to an 8051 microcontroller (intel 80C51-BH)

The RAM and ROM has a write pin at #27, a read pin at #22 and a chip enable pin at #20. All of these pins are considered enabled when logic low is applied.

The problem I seem to have is that all of the control pins are between the data and address pins of all devices, which makes interfacing a problem.

Also, it seems to me that it is more optimal to reverse the ram and rom so VCC is on the opposite side, but I'm a little lost.

I'm also using a single sided photo resist covered board.

List of 42 messages in thread
TopicAuthorDate
My 8051 project failed. Help me recover please.            01/01/70 00:00      
   Wrong questions            01/01/70 00:00      
      omg            01/01/70 00:00      
         You\'re looking in the wrong place            01/01/70 00:00      
            I explain            01/01/70 00:00      
   under-/overexposure?            01/01/70 00:00      
   Test exposure            01/01/70 00:00      
      Nice...            01/01/70 00:00      
   Developer            01/01/70 00:00      
      If you're using software ...            01/01/70 00:00      
         answer            01/01/70 00:00      
            How do you transfer your image to the board?            01/01/70 00:00      
               done            01/01/70 00:00      
                  Just how do you know that?            01/01/70 00:00      
                     answer            01/01/70 00:00      
                        You need to examine it with a microscope.            01/01/70 00:00      
                        Been there done that.            01/01/70 00:00      
      Hypering ?            01/01/70 00:00      
         hypering            01/01/70 00:00      
            Future is...dark ?            01/01/70 00:00      
   Press-N-Peel            01/01/70 00:00      
      Maybe...            01/01/70 00:00      
      nah            01/01/70 00:00      
         Iron on...            01/01/70 00:00      
            Me too...            01/01/70 00:00      
               Me Three ...            01/01/70 00:00      
                  Press-N-Pell works GREAT!            01/01/70 00:00      
                     You mean like...            01/01/70 00:00      
   ABOUT THE DISTANCE BEETWEEN 2PIN            01/01/70 00:00      
      2.5mm?            01/01/70 00:00      
         Read the score - he's wrong!            01/01/70 00:00      
      Exclusive limit            01/01/70 00:00      
         Elusive truths ...            01/01/70 00:00      
            Very true.            01/01/70 00:00      
               With one layer, well the reg problems go away            01/01/70 00:00      
         width            01/01/70 00:00      
            Port?            01/01/70 00:00      
               answer            01/01/70 00:00      
                  They are Connectors - not Ports            01/01/70 00:00      
                  FYI - Those are shell-sizes            01/01/70 00:00      
                     FYFI - It still is the standard            01/01/70 00:00      
                     The same script            01/01/70 00:00      

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