'disconnect ARM from GP0. - 1000Hz / 1500Hz Square Wave
SetPin gp0,pio1
SetPin gp2,dout

'configure pio1
p=Pio(pinctrl 0,1,,,,gp0,)
e=Pio(execctrl gp2,0,31)
f=1000 * 6 'Hz

'line code comment
' 0   E081 SET GP0 output
' 1   E001      SET gp0 high
' 2   00C5      JMP (GP2=1) to 5, (skip instructions 3 & 4)
' 3   E001      SET gp0 high
' 4   E000      SET gp0 low
' 5   E000      SET gp0 low
' 6   0001      JMP to 1


'program pio1
PIO program line 1,0,&hE081
PIO program line 1,1,&hE001
PIO program line 1,2,&h00C5
PIO program line 1,3,&hE001
PIO program line 1,4,&hE000
PIO program line 1,5,&hE000
PIO program line 1,6,&h0001


'write the configuration (note we added "e")
PIO init machine 1,0,f,p,e,,0

'start the pio1 code
PIO start 1,0


'toggle GP2 in MMBasic
SetPin gp8,fin

Do
Pin(gp2) = Not Pin(gp2) 'toggle pin GP2
Print Pin(gp8)
Pause 2000
Loop

End

RC6
void KBDIntEnable(int status)
{
 PinSetBit(Option.KEYBOARD_CLOCK, TRISSET); // if tris = 1 then it is an input
 PinSetBit(Option.KEYBOARD_CLOCK, TRISSET);  // if tris = 1 then it is an input
 PinSetBit(Option.KEYBOARD_CLOCK, CNPUSET); // if tris = 1 then it is an input
 PinSetBit(Option.KEYBOARD_DATA, CNPUSET);  // if tris = 1 then it is an input
 if (status)
 ......

void  MIPS16 STR_REPLACE(char *target, const char *needle, const char *replacement){
char *ip=target;
int toggle=0;
   char comment[STRINGSIZE]={0};
   skipspace(ip);
   if(!(toupper(*ip)=='R' && toupper(ip[1])=='E' && toupper(ip[2])=='M' )){
       while(*ip){
           if(*ip==34){
               if(toggle==0)toggle=1;
               else toggle=0;
           }
           if(toggle && *ip==' '){
               *ip=0xFF;
           }
           if(toggle && *ip=='.'){
               *ip=0xFE;
           }
           if(toggle && *ip=='='){
               *ip=0xFD;
           }
           if(toggle==0 && *ip=='\''){
               strcpy(comment,ip);
               *ip=0;
               break;
           }
           ip++;
       }
       str_replace(target, needle, replacement);
       ip=target;
       if(comment[0]=='\''){
           strcat(target,comment);
       }
       while(*ip){
           if(*ip==0xFF)*ip=' ';
           if(*ip==0xFE)*ip='.';
           if(*ip==0xFD)*ip='=';
           ip++;
       }
   }

}

STR_REPLACE(inpbuf,"=>",">=");
STR_REPLACE(inpbuf,"ERASE ","CLEAR VARS ");
STR_REPLACE(inpbuf,"MM.FONTHEIGHT","MM.INFO(FONTHEIGHT)");
STR_REPLACE(inpbuf,"HEX$(","BASE$(16,");

SYSTEM command-line$

This will exit to Shell, run the 'command-line$' as if typed in at the command
prompt and then return to the loading MMBasic program.
This can be used to access features of the Commamd prompt Shell that are not available
from within MMBasic.

Option ESCAPE
SYSTEM "Files \q*.TXT\q,size"