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Error when trying to write to a variable using inline assemb

 
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Zvoc47

Bascom Member



Joined: 02 Apr 2015
Posts: 21

PostPosted: Tue Apr 07, 2015 9:26 am    Post subject: Error when trying to write to a variable using inline assemb Reply with quote

I want to write the stack pointer to the variables StkL and StkH. The error I get is that BASCOM is expecting a label instead of a variable. If I use {}, I'll only get one byte of the address, but I want to get both low and high bytes.
Code:
Dim StkL As Byte
Dim StkH As Byte
$asm
LDS r16, SPL
LDS r17, SPH
LDI r30, LOW(StkL)
LDI r31, HIGH(StkL)
ST X, r16
ldi r30, LOW(StkH)
Ldi r31, HIGH(StkH)
st X, r17
$end asm

Can you help me?

(BASCOM-AVR version : 2.0.7.8 )
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Zvoc47

Bascom Member



Joined: 02 Apr 2015
Posts: 21

PostPosted: Tue Apr 07, 2015 9:43 am    Post subject: Reply with quote

Solved it myself. It gave me zeros in the simulator, but on real MCU, the values were correct. The simulator failed to simulate $3D and $3E which are the CPU_SPL and CPU_SPH. Please fix this.

My code was:
Code:
Dim StkL As Byte
Dim StkH As Byte
LOADADR StkL, Z
$asm
lds r16, $3D
ST Z, r16
$end asm
LOADADR StkH, Z
$asm
lds r16, $3E
ST Z, r16
$end asm
Print "Prvo SPH=";StkH;" SPL=";StkL
SPH=$2F
LOADADR StkL, Z
$asm
lds r16, $3D
ST Z, r16
$end asm
LOADADR StkH, Z
$asm
lds r16, $3E
ST Z, r16
$end asm
Print "Drugo SPH=";StkH;" SPL=";StkL
Enable Interrupts  
Print "Hello World!"
Stop
[/code]
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albertsm

Administrator



Joined: 09 Apr 2004
Posts: 4975
Location: Holland

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PostPosted: Tue Apr 07, 2015 9:24 pm    Post subject: Reply with quote

why so complex?
Dim StkL As Byte
Dim StkH As Byte
stkl = SPL
stkh = SPH

or :
dim wSTK as Word
wSTk=SP ' sp is defined as word too

About the sim : i will change it. the memory offset of the registers is not available in xmega and thus lower regs are pointing to the wrong memory.

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