fatal: out of memory (pbpw.exe)

[HenrikOlsson]

The pic im using is a PIC18LF46K22 and it does have an MSSP module. Just a question on using the MSSP in terms of speed, are we talking 2x 3x 4x speed increase. I can currently completely fill the screen in less than a second.

Hi, it's my understanding that SHIFTOUT runs at 50kHz with a 4MHz oscillator and then scales linearly with increased oscillator speed, but I'm not 100% sure on that. The MSSP module can run at Fosc/4 which at 4Mhz is 20 times faster than SHIFTOUT.

Now, the code must be able to keep up with the increased speed, and must be able to feed the MSSP module with data to shift out. Basically you have only 8 instructioncyles to get the next byte and then load it to the MSSP module as soon as there's room in its output register. If you're not able to do it in 8 cycles the overall thruput will drop - obviously.

So, just because the "clock" runs 20times fater than SHIFTOUT I don't think you should expect a 20 times increase, somewhere around 5-10 sounds more realistic.

/Henrik.

[Sphere]

Thanks all for the replies. Now where's that darn lookup table gone.

Cheers Sphere.

[mister_e]

something like that should give some hints

        goto init
        ASM
        ifdef BSR
PIC_TYPE = 2 ; 2=PIC18
        else
PIC_TYPE = 1 ; 1=PIC16
        endif
        
;%00000001,10,%11111111,%10000001,%11111111,%11111111,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000, %00000000]
tbl10   dt 1,10, b'11111111',b'10000001',b'11111111',b'11111111', 0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0   
        dt 0,0
             
;11,%11111111,%00111100,%11111111,%11111111,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000]
tbl11   dt 11, b'11111111',b'00111100',b'11111111',b'11111111',0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0   
        dt 0
 
;12,%11111111,%00111100,%11111111,%11111111,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000, 
;%00000000]
tbl12   dt 12,b'11111111',b'00111100',b'11111111',b'11111111', 0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0  
        dt 0

;13,%11111111,%00000000,%11111111,%11111111,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000]
tbl13   dt 13, b'11111111',0,b'11111111',b'11111111',0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0  
        dt 0

;14,%11111111,%00000000,%11111111,%11111111,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000, 
;%00000000]
tbl14   dt 14, b'11111111',0,b'11111111',b'11111111',0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0  
        dt 0

;15,%11111111,%00111100,%11111111,%11111111,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000, 
;%00000000]
tbl15  dt 15, b'11111111',b'00111100',b'11111111',b'11111111',0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0  
        dt 0

;16,%11111111,%00111100,%11111111,%11111111,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000, 
;%00000000]
tbl16   dt 16, b'11111111',b'00111100',b'11111111',b'11111111',0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0  
        dt 0

;17,%11111111,%00111100,%11111111,%11111111,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,%00000000,
;%00000000,%00000001]
tbl17   dt 17, b'11111111',b'00111100',b'11111111',b'11111111',0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0
        dt 0,0,0,0,0,0,0,0,0,0  
        dt 0,1
        
tblend = $ - PIC_TYPE

        endasm
init:
        PIC_TYPE    CON EXT
        tbl10       CON EXT 
        tbl11       CON EXT 
        tbl12       CON EXT 
        tbl13       CON EXT 
        tbl14       CON EXT 
        tbl15       CON EXT 
        tbl16       CON EXT 
        tbl17       CON EXT 
        tblend      CON EXT 
        addr        VAR WORD
        dta         VAR BYTE
        cntr        VAR BYTE
        
        CLEAR
        TRISC = 0
        TRISB = 0
        PAUSE 50
        
MAIN:   
        HIGH PORTB.2 'CHIP SELECT
        FOR addr=tbl10 TO tblend STEP PIC_TYPE
                READCODE addr, dta
                SHIFTOUT portb.1, portb.0,0,[dta]
                cntr=cntr+1
                HSEROUT ["%",BIN8 dta,", "]
                IF cntr=10 THEN
                        HSEROUT [13,10]
                        cntr=0
                        ENDIF
                NEXT
        LOW  PORTB.2 'CHIP SELECT
        HSEROUT [13,10,"----- done ------<", 13,10,_
                dec ((tblend-tbl10)/PIC_TYPE), " Byte sent>"]
                
HERE:   GOTO HERE

there's still room for improvement.