In SX Microcontrollers, SX/B Compiler and SX-Key Tool, metron9 wrote:

Hey I guess that's why time critical stuff I like Assembler.

This was just a quick check to see what speed it was operating at as T&E had asked if i used a resonator rot the 50mhz test I did on his project. I originally thought I had read the sxkey generates the 50mhz and it does.


So T&E, the sxkey itself generates 50mhz when told to do so by the device settings. The internal 4mhz to 32khz is the internal oscillator on the chip. Generally you do not want to use the internal oscillator for serial communications because it is not precise enough on the ATMEL parts I have worked with. I don't know the stability of the sx internal oscillator. In your project you ace clocking the sata out so it doesn't matter.

Picture, you can see the first red line on off is 200ns and the second one is actually 2 clock cycles or 40ns starting on the rising edge of the clock signal.  I only have a 100mhz scope so measuring 50mhz is the limit due to some guys law I forgot his name, Bean knows.

Curious why the same machine code instruction is genersted by SX/B in both lines 195 and 201, as well as 203, and 209 for the LOW command, anyone know?




[code]
 =0000004C       XXX:                             ;XXX:
   194                  
   195  004C  0586        SETB CS1_8255                  ;high cs1_8255
   196  004D  0CFB        MOV FSR,#__TRISB              
        004E  0024
   197  004F  0480        CLRB IND.4                    
   198  0050  005F        MODE $0F                      
   199  0051  0200        MOV !RB,IND                   
        0052  0006
   200  0053  0018        BANK $00                      
   201  0054  0586        SETB CS1_8255                 
   202                  
   203  0055  0486        CLRB CS1_8255                  ;low cs1_8255
   204  0056  0CFB        MOV FSR,#__TRISB              
        0057  0024
   205  0058  0480        CLRB IND.4                    
   206  0059  005F        MODE $0F                      
   207  005A  0200        MOV !RB,IND                   
        005B  0006
   208  005C  0018        BANK $00                      
   209  005D  0486        CLRB CS1_8255                 
   210                  
   211  005E  0586        SETB rb.4                      ;rb.4=1
   212                  
   213  005F  0486        CLRB rb.4                      ;rb.4=0
   214                  
   215  0060  0010        JMP @xxx                       ;goto xxx
        0061  0A4C
   216                  
[/code]

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