unsuccessfull until now
I've been working on this for hours now, unsuccesfully
Finally, I reduced my code to a minimum and started some readings on the scope. In fact, the current aim is now to make sure the PIC is working as it should - not matter what data/command is sent. I'm trying to get something like this (from the display's datasheet):
..but this is what I see on my scope (where SDO=SI and SCK=SCL):
At a very first glance, one can see that the SCK (SCL) doesn't "tick" as it should. I even tried another PIC but no change.
I have checked and re-checked the hardware (connections and wiring) many times and I think I haven't missed something there. I also put 10k pull-down resistors on all four wires but this didn't make any difference.
Here's my "non-efficient" but as simple and readable as possible code.
It looks like something is missing in the SSP setup; what is it?Code:<html><head></head><body><!--StartFragment--><pre><code><font color="#000080"><i>' PIC 16F690 Fuses </i></font><font color="#008000">@ DEVICE FCMEN_OFF @ DEVICE IESO_OFF @ DEVICE BOD_OFF @ DEVICE CPD_OFF @ DEVICE PROTECT_OFF @ DEVICE MCLR_OFF @ DEVICE PWRT_OFF @ DEVICE WDT_OFF @ DEVICE INTRC_OSC_NOCLKOUT </font><font color="#000080"><i>' Registers 76543210 </i></font>OPTION_REG = %10000000 <font color="#000080"><i>'PORT A&B Pull-Ups disabled (look WPUA & WPUB) </i></font>OSCCON = %01100000 <font color="#000080"><i>'Internal RC set to 4Mhz </i></font>ANSEL = %00000000 <font color="#000080"><i>'Disable analog inputs Channels 0 to 7 </i></font>ANSELH = %00000000 <font color="#000080"><i>'Disable analog inputs Channels 8 to 11 </i></font>WPUB = %00000000 <font color="#000080"><i>'Disable weak pull-ups </i></font>ADCON0 = %00000000 <font color="#000080"><i>'A/D Module is OFF </i></font>CM1CON0 = %00000000 <font color="#000080"><i>'Comparator1 Module is OFF </i></font>CM2CON0 = %00000000 <font color="#000080"><i>'Comparator2 Module is OFF </i></font>INTCON = %00000000 <font color="#000080"><i>'INTerrupts CONtrol </i></font>TRISA = %00000000 <font color="#000080"><i>'Set Input/Output (0 to 5) </i></font>PORTA = %00000000 <font color="#000080"><i>'Ports High/Low (0 to 5) </i></font>TRISB = %00000000 <font color="#000080"><i>'Set Input/Output (4 to 7) </i></font>PORTB = %00000000 <font color="#000080"><i>'Ports High/Low (4 to 7) </i></font>TRISC = %00000000 <font color="#000080"><i>'Set Input/Output (0 to 7) </i></font>PORTC = %00000000 <font color="#000080"><i>'Ports High/Low (0 to 7) 'setup SPI master mode </i></font>SSPSTAT.6 = 1 <font color="#000080"><i>'Data transmitted on rising edge of SCK </i></font>SSPCON.5 = 1 <font color="#000080"><i>'SSP is enabled </i></font>SSPCON.4 = 0 <font color="#000080"><i>'Idle state for clock is a low level </i></font>SSPCON.1 = 1 <font color="#000080"><i>'SPI Master mode, clock = FOSC/64 '------------------------------------------------------------------------------- </i></font>INIT: RS <b>VAR </b>PORTB.5 <font color="#000080"><i>'instruction=0 / data=1 </i></font>SCK <b>VAR </b>PORTB.6 <font color="#000080"><i>'Clock pin </i></font>CSB <b>VAR </b>PORTB.7 <font color="#000080"><i>'LOW active pin </i></font>SDO <b>VAR </b>PORTC.7 <font color="#000080"><i>'Data Out pin </i></font>Mode <b>CON </b>1 <font color="#000080"><i>'MSBFIRST - Clock idles low. '------------------------------------------------------------------------------- </i></font><b>PAUSE </b>1000 <font color="#000080"><i>'Time to settle display's Vdd </i></font>MAIN: <b>LOW </b>CSB <font color="#000080"><i>'set LCD active </i></font><b>PAUSE </b>40 <b>LOW </b>RS <font color="#000080"><i>'set Register to "instruction" </i></font><b>PAUSEUS </b>3 <b>SHIFTOUT </b>SDO,SCK,Mode,[$39] <b>PAUSE </b>30 <b>HIGH </b>CSB <b>PAUSE </b>30 <b>GOTO </b>MAIN: <b>END</b></code></pre><!--EndFragment--></body></html>
The error must be obvious, but I can't see where the fish is!
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