Nokia lcd include , small footprint to suit pic16's

[richard]

mike

mssp is pretty easy


SSP1CON1=0x21 ;$22,21,20 all work @32mhz 20 is fastest
SSP1STAT=0x40
sdo and sck pins set to dig o/p


to transfer data
PIR1.3=0
SSP1BUF = data
WHILE (!PIR1.3) ;

tried your code on 16f1847 ,its not working

[Mike, K8LH]

It seems XC8 is placing my program code on top of my font table in the 0700h area of memory. More detective work (sigh)...

Thanks for the MSSP/SPI info, Richard. I will get to that after tracking down the current problem...

Mike

<added>

If you get a chance, add the "ovrld" param' to the following line and tell me if that fixes the problem, please?

   PSECT myFonts, class=CODE, abs, ovrld, space=0, delta=2
                                   ^^^^^

[richard]

ovrld,

does not fix it
even local too

there is more wrong than just that , the putwreg function is getting called six times for the wrchar
and only 5 times for the entire putstr call
its a total bitch to debug with all that inline asm , the debugger just
goes stupid

putcmd looks fine on the logic analyser , it all goes pear shaped from then on

[Mike, K8LH]

Sorry, Richard (and gang). A bug at the very top of the putchar() routine was messing up the font table address. And yes, I know assembler is a PITA... I wish I could get a gratis copy of PBP...

Corrected version attached (375 words total). I still need to dig out my old Nokia 5110 display and test this on real hardware. I also have a tiny 128x32 I2C OLED display and a tiny 128x64 SPI OLED display to play with sometime soon.

Cheerful regards, Mike

Nokia_Main.c.txt

[richard]

putstr still not working

I think it should look like this, but it only works for the first call
so I get "Re and then garbage

 void putstr(const char *str)     // put 'ROM' strings
   {                     //
     while(*str) 
       wrchar(*str++);
   }                                //

[richard]

more oddly

strcpy(buff,"eady");


putstr(buff);

works with my modified routine


putstr("eady");
crashes the show

[richard]

void wrchar(char d)          //
   { 
     volatile char ascii=d;

fixed it, compiler optimised ascii var out

[Mike, K8LH]

Yes, your putstr() routine is better...

While debugging I've found XC8 is using the same memory location for local variables in both the wrchar() and putstr() functions. The wrchar@ascii variable is using 70h and the putstr@str pointer is using 70h and 71h. Is this a result of my heavy use of assembly code? That is, XC8 doesn't realize those local variables need to be unique? How do I get XC8 to use unique memory locations for those local variables?

[richard]

make them static