PIC18FxxQ43 Version of DT_INTS

[longpole001]

i am finding some other issues with bank access with other asm code i have , that is not happy on q43

thinking that what you did with
-----------
movf BSR, 0
banksel INT_Priority_Reg
bsf INT_Priority_Reg, INT_Priority_Bit
movwf BSR
-----------

historic code i use for elasped timer to get the cycles constant and limited may now work against q43 chip ??

i may be wrong as my asm really sucks but each command that has BCF will need a banksel , bsf ????

having trouble with load of timer1 using asm on the q43

but doing that change would add cycles i am sure

i hope i am wrong

 ASM
                                 ; 16.368mhz tcxo = 61.0948ns clock       16.00Mhz = 62.5 ( internal osc used currenlty 20/2/20)
TimerConst = 40912               ; 40912 + 8 cycle instrution load = 40920 x 61.0948ns = 2.499999216mS  timer 1 clock tick   (  16mhz int = 39992 + 8cycle = 40000 x 62.5ns = 2.5ms) 
TimerConst = 65536 - TimerConst  ; set value for timer1 preload
                                                           
;-----------------  ADD TimerConst to TMR1H:TMR1L -------------------------
ADD2_TIMER   macro
     BCF     T1CON,TMR1ON, 0       ;  1 Turn off timer
     MOVLW   LOW(TimerConst)       ;  1
     ADDWF   TMR1L,F, 0            ;  1    
     BTFSC   STATUS,C              ;  1/2
     INCF    TMR1H,F, 0            ;  1
     MOVLW   HIGH(TimerConst)      ;  1
     ADDWF   TMR1H,F, 0            ;  1
     endm

; -----------------  ADD TimerConst to TMR1H:TMR1L and restart TIMER1 ------
RELOAD_TIMER  macro
     ADD2_TIMER
     BSF     T1CON,TMR1ON, 0       ;  1   Turn TIMER1 back on  (8 cycles)
     endm

; -----------------  Load TimerConst into TMR1H:TMR1L ----------------------
LOAD_TIMER  macro
     MOVE?CT  0, T1CON,TMR1ON
     MOVE?CB  0, TMR1L
     MOVE?CB  0, TMR1H
     ADD2_TIMER
     endm
 ENDASM

[tumbleweed]

On the Q43 (and most recent PIC18's with the VIC), the SFR registers have been moved down in memory starting at BANK 0,
so general purpose RAM no longer starts there. The access bank used to be part of that, but no more.

For the Q43, the access RAM is now at 0x500-0x55F, and the SFR access bank is 0x460-0x4FF.
Anything located outside those addresses require the bank select register (BSR) to be set appropriately.

Many asm instructions have a ", a" field at the end, where 'a' specifies the RAM access bit:
a = 0: RAM location in Access RAM (BSR register is ignored)
a = 1: RAM bank is specified by BSR register

The TMR1 registers are located in bank 3, so you can't use asm instructions that end in ", 0" to access them.
You'd have to set the BSR with a 'movlb' (or use mpasm 'BANKSEL reg') and change the ", 0" to ", 1" (or drop it off).
If you don't specify the ", a" part MPASM is usually pretty good at figuring out when it needs a = ", 0", or ", 1", but it's up to you to set the BSR if needed.

Datasheet sections 44 (Instruction Set Summary) and section 46 (Register Summary) have all the info you need, once you get your head wrapped around how it works.


So, looking at your timer macros LOAD_TIMER is probably ok since the 'MOVE?xx' macros set the BSR, but if the other two are used on their own they'll need to change (adding instructions which will change the timing).

[longpole001]

ok tubleweed ,

will try some add in commands for timer 1

hope you shine a light on the low priority ints problem

cheers

sheldon

[longpole001]

Hi guys

is there any further tests i can do to help solve the low priory ints problem on the q43 chip

cheers

sheldon

[tumbleweed]

Not really that I can think of.

I thought I'd try and load it into MPLABX so I could debug it, but it's been so long since I've used it w/PBP I can't seem to get the two so I can build and debug in MPLABX.
Using MPLABX 5.35 w/ PBP 3.1.4, a simple blinky program builds ok with the commandline, but even though it builds in MPLABX it fails the MPLABX make process so it won't load it.

I don't remember what makes the two happy...

[richard]

I don't remember what makes the two happy...

You need to travel back in time ten years , last known semi workable setup was with mplabx 2.35

[tumbleweed]

I don't need the editor to work or anything... just be able to compile and load it so I can debug, even at the asm level.
I thought that part still worked, but maybe I'll try treating it as an asm project and do it that way.