| View previous topic :: View next topic | 
	
	
		| Author | Message | 
	
		| pekka1234 
 
 
 Joined: 28 May 2017
 Posts: 106
 
 
 
			    
 
 | 
			
				| Mitutoyo |  
				|  Posted: Thu Nov 28, 2024 10:02 am |   |  
				| 
 |  
				| Ttelmah You know exactly as it should be.
 
 I have tried with four micrometer devices and asked help from Mitutoyo, but no answer.
 
 There is some problem.
 
 I can't find any information of RD, CLOCK. DATA and REQUEST.
 As I told I have done on a reading device 1988 to PC  and it worked well.
 The oldest device is as old as.
 
 I have tried PowerFIX Z22855F micrometer. It is quite similar to Mitotoyo-
 It has 3V battery and Mitotoyo has 1.5V battery.
 
 The ready made Mitutoyo PC read device costs about 200 e.
 
 And my customer needs three of these.
 
 A quite job, but nothing done.
 
 Pekka
 |  | 
	
		|  | 
	
		| temtronic 
 
 
 Joined: 01 Jul 2010
 Posts: 9589
 Location: Greensville,Ontario
 
 
			    
 
 | 
			
				|  |  
				|  Posted: Thu Nov 28, 2024 5:22 pm |   |  
				| 
 |  
				| 1st step.. get the correct hardware interface ! You MUST use some form of logic level conversion to convert Mitty 1.5V levels to PIC 5 volt and PIC 5 volt to Mitty 1.5v. Also be sure a Mitty 'high' gives a PIC 'high' and NOT a PIC 'low' signal. 
 2nd step, cut the code.
 
 NO amount of code (software ) will correct bad or wrong hardware.
 |  | 
	
		|  | 
	
		| Ttelmah 
 
 
 Joined: 11 Mar 2010
 Posts: 19967
 
 
 
			    
 
 | 
			
				|  |  
				|  Posted: Fri Nov 29, 2024 7:37 am |   |  
				| 
 |  
				| In his original thread he has the hardware on the wrong pins, and is using a transistor not a FET for the pulldown. Mitutoyo in their application note
 on this say a FET is required, since a transistor won't pull the signal down low
 enough.
 The reversal though is the real problem. He talks as if REQ should go low.
 It doesn't. The PIC has to _pull_ REQ low. It is this that starts the
 transaction. It has to be pulled below 0.4v to trigger the start.
 |  | 
	
		|  | 
	
		|  |