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tritonium · 2019-09-09 23:18

Hi

I'm using the rctime function to read a thermistor (in conjunction with a 0.1uf capacitor).
It works great in cog mode but not in LMM mode.

Dave

Bean · 2019-09-10 12:25

Dave,
I will look into it and let you know what I find.

Bean

Bean · 2019-09-10 12:40

Dave,
Looking at the source code I don't see any issues.
Can you post a a little of your code ? And maybe the section of .spin (pasm) code that it generates ?
That would help a lot.

Bean

tritonium · 2019-09-10 19:21

Hi
I expect its to do with the waitcnt . Maybe 80 clocks is not long enough for LMM to complete.
Its seems to print gibberish ever 50 or so seconds (nowhere near exactly that) which is about how long it takes to count 2^32 at 80Mhz.

'test of rctime on thermister 10k ohm at 25 degs c
'220 ohm resisitor from pin 24 to thermister and 0.1 uF cap in parallel-other end to 0v
DEVICE P8X32A, XTAL1, PLL16X
FREQ 80_000_000

therm	PIN  24 low			


pcrlf		SUB 0
sertx		SUB 1
print		SUB 1
pstr		SUB 1

strslt	hub string(20)

temp	var	long
stmp1	var	long
stmp2	var	long



' ======================================================================
' this works- LMM doesn't (bet I've done something daft!!!!)
  PROGRAM Start  'LMM
 
' ======================================================================

START:
pause 5000
pstr "starting"
pcrlf

do
high therm
pause 5
rctime therm,1,temp 
print temp
pstr " "
pause 1000
loop
end


'========== SUBS ===========================
sub pstr	'send serial string
stmp1=__param1
do
	rdbyte stmp1,stmp2
	if stmp2=0 then exit
	sertx stmp2
	inc stmp1
loop
endsub
'----------------
sub print
	strslt=str __param1,8
	pstr strslt
endsub
'------------------------

sub sertx	'send serial byte
	SEROUT 30,T9600,__param1
endsub

'---------------------------
sub pcrlf
	sertx 13
	sertx 10
endsub

the relevant spin bits....
cog version:-

mov           __temp2,#5                   'pause 5
                  mov           __temp1,_1mSec              
                  add           __temp1,cnt                 
__L0002                                                     
                  waitcnt       __temp1,_1mSec              
                  djnz          __temp2,#__L0002            

                  mov           __temp1,therm                'rctime therm,1,temp 
                  andn          dira,__temp1                
                  mov           temp,#0                     
                  mov           __temp2,cnt                 
                  adds          __temp2,#80                 
__L0003                                                     
                  adds          temp,#1                     
                  waitcnt       __temp2,#80                 
                  and           __temp1,ina NR, WZ          
    IF_NZ         jmp           #__L0003                    

                  mov           __param1,temp                'print temp
                  call          #print

This is LMM version:-

mov           __temp2,#5                   'pause 5
                  mov           __temp1,_1mSec              
                  add           __temp1,cnt                 
__L0002                                                     
                  waitcnt       __temp1,_1mSec              
                  djnz          __temp2,#_LMM_JUMP          
                  long          @@@__L0002                  

                  mov           __temp1,therm                'rctime therm,1,temp 
                  andn          dira,__temp1                
                  mov           temp,#0                     
                  mov           __temp2,cnt                 
                  adds          __temp2,#80                 
__L0003                                                     
                  adds          temp,#1                     
                  waitcnt       __temp2,#80                 
                  and           __temp1,ina NR, WZ          
    IF_NZ         sub           __PC,#(($-__L0003)*4)+4     

                  mov           __param1,temp                'print temp

Hope that helps

Dave

Bean · 2019-09-11 12:42

Dave,
You are correct. 80 clocks is not quite enough time to get through the loop in LMM.
I will have to change RCTIME to measure in 2uSec increments.
As a workaround you could use in-line assembly.

ASM
                  mov           __temp1,therm                'rctime therm,1,temp 
                  andn          dira,__temp1                
                  mov           temp,#0                     
                  mov           __temp2,cnt                 
                  adds          __temp2,#160                 
__RCTIMEFIX                                                     
                  adds          temp,#1                     
                  waitcnt       __temp2,#160                 
                  and           __temp1,ina NR, WZ          
    IF_NZ         sub           __PC,#(($-__RCTIMEFIX)*4)+4     
ENDASM

If you try it, let me know if it works.
Remember the value will be in 2uSec units instead of 1uSec units.

Bean

tritonium · 2019-09-11 21:59

Hi again

Yes that works- BUT- got another

it seems in LMM one byte strings are corrupt- I have an example

DEVICE P8X32A, XTAL1, PLL16X
FREQ 80_000_000


strslt	hub string(20)

stmp1	var	long
stmp2	var	long


pcrlf		SUB 0
sertx		SUB 1
print		SUB 1
pstr		SUB 1


' ======================================================================
  PROGRAM Start  LMM
' ======================================================================

START:

pause 5000
pstr "starting"
pcrlf
do
	pcrlf
	pstr "hello"
	pstr " "
	pstr "Dave"
	pstr "a"
	pstr "bb"
	pause 1000
loop
end

'========== SUBS ===========================

sub pstr	'send serial string
stmp1=__param1
do
	rdbyte stmp1,stmp2
	if stmp2=0 then exit
	'phex stmp2
	sertx stmp2
	inc stmp1
loop
endsub
'----------------
sub print
	strslt=str __param1,8
	pstr strslt
endsub
'------------------------

sub sertx	'send serial byte
	SEROUT 30,T9600,__param1
endsub

'---------------------------
sub pcrlf
	sertx 13
	sertx 10
endsub

produces...

starting

hello&L(Davebb
hello&L(Davebb
hello&L(Davebb
hello&L(Davebb
hello&L(Davebb
hello&L(Davebb
hello&L(Davebb
hello&L(Davebb
hello&L(Davebb
hello&L(Davebb
hello&L(Davebb

as you can see the one byte string " " and "a" are problematic while the longer ones are fine.
The " " string with one space in produces &L( and the "a" produces nothing at all!

Thanks for looking into these querks- really appreciate all your hard work.

Dave

Bean · 2019-09-12 00:44

In PropBasic a single character in quotes is a byte value.
More than one character produces a pointer to the address of the string.
If you want to pass a single character to a SUB that is expecting a string you can append \000.

You would have to use:
pstr " \000" for space or pstr "a\000" for "a".

You might get away with testing the parameter to see if it is less than 128 because strings are stored at the end of the program (I think...) so as long as there is at least 128 bytes of code, it should work.

sub pstr	'send serial string
  IF __param1 < 128 THEN
    SERTX __param1
  ELSE
    stmp1=__param1
    do
	rdbyte stmp1,stmp2
	if stmp2=0 then exit
	'phex stmp2
	sertx stmp2
	inc stmp1
    loop
  ENDIF
endsub

Bean

tritonium · 2019-09-21 20:29

Hi

Thanks for explaining- I have another question regarding LMM
While running in LMM mode how much of the cog is used to "run" the LMM code (which can, I assume use the whole of the hub- barring hub variables etc.) and how much is left for cog vars? I am writing some code that 'could' use a large number of instant access cog vars but 'could' instead use hub variables, but at the expense of 'looking' less obvious. If you say there is enough room for 150 cog vars left while running LMM that might do. Hope I explained that clearly!

edit/
Also, whereas I can access hub variables by using a name or index from a base variable- can this be done in the cog vars. If I define an array date_time(7) VAR LONG then each long can be indexed, but if I want to also directly acces via year, month, day, etc is there a way- I cant assign a name to each of the indexed vars.

Dave

Bean · 2019-09-22 12:26

The cog code to run LMM is pretty minimum. There should be plenty of room for 150 longs.
I don't recommend using COG arrays, it requires self-modifying-code and uses precious code space (for non-LMM code).
I never use cog arrays, so I'm not sure if this will work but you can try:

name VAR LONG MyArray(2)

to create an alias.

Bean

tritonium · 2019-09-22 15:59

Hi Bean

Thanks- pretty much as I thought.
Having lots of fun trying to convert some pbasic code to prop. Its all quite do-able but looks rather different. I know propbasic has some commands like rctime and PULSOUT, pause etc and others have made libraries and examples of alternatives to lookup, lookdown etc, to achieve the same ends- all is good.

Dave

tritonium · 2019-10-31 00:27

Hi again

Is there a way to restart the basic program- resetting stack etc as in the 'RUN' command of old.
Will entering 'goto start' achieve this?

Dave

Bean · 2019-10-31 12:18

Unless you are using LMM there is no stack.

In LMM you should be able to reset the call stack by doing:

asm
  MOV __STACKPTR,#__STACK
endasm

Bean

Download PropBasic Version 1.48 (Aug 9, 2018) Here...

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