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???
07/31/05 10:47
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 		 #98503 - connections and timings
Responding to: ???'s previous message
hi,

the first question: is pin 15 (Clock Inhibit) connected correct? This pin should be tied to GND.

Now about the code:
Save This Code
clr port0.1 ;clock 
nop 
nop 
setb port0.1 
mov c,port0.0

As I understand these NOPs are required by TW timing. But what is about propagation delay TPLH? Data comes to output after rising clock edge + propagation delay. In your code there is no NOPs between rising edge and data loading. I suggest you to insert appropriate number of NOPs:
Save This Code
setb port0.1 
; insert NOPs here
mov c,port0.0


Regards,
Oleg

List of 28 messages in thread
TopicAuthorDate
74hc165 read problem            01/01/70 00:00      
   pull ps?            01/01/70 00:00      
      external pull up            01/01/70 00:00      
   74LS165 schematic and assembly program            01/01/70 00:00      
      re 74LS165 schematic and assembly progra            01/01/70 00:00      
   connections and timings            01/01/70 00:00      
      Port0 can show very high rise times            01/01/70 00:00      
      thanks oleg and kai            01/01/70 00:00      
      re connections and timings            01/01/70 00:00      
         What pull-ups?            01/01/70 00:00      
            Also....            01/01/70 00:00      
               re also            01/01/70 00:00      
                  Very strange...            01/01/70 00:00      
                     re Very strange...            01/01/70 00:00      
                        Something wrong with 74HC165?            01/01/70 00:00      
                           If you have an oscilloscope..            01/01/70 00:00      
                              re If you have an oscilloscope..            01/01/70 00:00      
            re What pull-ups?            01/01/70 00:00      
               HC vs HCT vs TTL            01/01/70 00:00      
   165 access problem            01/01/70 00:00      
   using opto to pulldown pin of 74hc165            01/01/70 00:00      
      which optocouplers            01/01/70 00:00      
      time for schematics            01/01/70 00:00      
   here is solution            01/01/70 00:00      
   it is working            01/01/70 00:00      
      because of something in your hardware            01/01/70 00:00      
         nop not due to hardware            01/01/70 00:00      
            still could be            01/01/70 00:00      

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