Subroutine call inside an ISR

SelfPropelled

It appears that calling a Subroutine from an Interrupt causes problems.
The SUB directive occurs after the ISR routine, so the Sub call generates
an 'unkown command' error.

Moving the SUB directive above the ISR routine causes other problems.

Am I missing something?

[noparse][[/noparse]code]
'==========================================================================
' INTERRUPT
'

---

ISR_Start:

PULSOUT RA.0, 1000 'FLASH TEST LED
PULSOUT RA.1, 1000
PULSOUT RA.2, 1000

READKEY ' <<< THIS GENERATES COMPILER ERROR 'UNKNOWN COMMAND'
ISR_Exit:

Keys = %0000_0000 'Set Key Row Drive low for WKED
WakePend = %0000_0000 'CLEAR INTERRUPT PENDING FLAG.
RETURNINT

'=========================================================================

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

'

---

' Program Code
'

---

READKEY SUB 0 ' <<< Is this in the right place?

Start:
TRIS_Keys = %1111_0000 ' refresh IO state
Keys = %0000_0000 ' Set Key Row Drive low for WKED
WKED_B = %1111_1111 ' Falling edge detect
WKEN_B = %0000_1111 ' Use bits 4-7 for inputs
ST_B = %0000_1111 ' Bits 4-7 are Schmitt Trigger Inputs

'...

'

---

SUB READKEY
.
.
.
ENDSUB


'=============================================================

Bean

You need to use GOTO

'==========================================================================
' INTERRUPT
' -------------------------------------------------------------------------


ISR_Start:
  GOTO ISR_Code
  
'=========================================================================

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

' -------------------------------------------------------------------------
' Program Code
' -------------------------------------------------------------------------

READKEY SUB 0 ' <<< Is this in the right place?

Start:
TRIS_Keys = %1111_0000 ' refresh IO state
Keys = %0000_0000 ' Set Key Row Drive low for WKED
WKED_B = %1111_1111 ' Falling edge detect
WKEN_B = %0000_1111 ' Use bits 4-7 for inputs
ST_B = %0000_1111 ' Bits 4-7 are Schmitt Trigger Inputs

'...

'-------------------------------------------------------------------------

 
ISR_Code:
 
PULSOUT RA.0, 1000 'FLASH TEST LED
PULSOUT RA.1, 1000 
PULSOUT RA.2, 1000 

READKEY ' <<< THIS GENERATES COMPILER ERROR 'UNKNOWN COMMAND'
ISR_Exit:

Keys = %0000_0000 'Set Key Row Drive low for WKED
WakePend = %0000_0000 'CLEAR INTERRUPT PENDING FLAG.
RETURNINT

SUB READKEY
.
. 
.
ENDSUB


'=============================================================

Bean


▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Use BASIC on the Propeller with the speed of assembly language.
PropBASIC thread http://forums.parallax.com/showthread.php?p=867134

March 2010 Nuts and Volts article·http://www.parallax.com/Portals/0/Downloads/docs/cols/nv/prop/col/nvp5.pdf
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
There are two rules in life:
· 1) Never divulge all information
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
If you choose not to decide, you still have made a choice. [noparse][[/noparse]RUSH - Freewill]

JonnyMac

To do this you have to move the ISR code below the SUB/FUNC definitions. The easiest way to do this is to add:

GOTO ISR_Handler

In the interrupt section -- this is the only thing there. Somewhere in your listing (usually after the main body of the program) you'll have this:

ISR_Handler:
  ' your code here
  RETURNINT

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Jon McPhalen
Hollywood, CA

SelfPropelled

TY Bean.
Much appreciated.
Mike

SelfPropelled

JonnyMac,
I missed your reply earlier.
Nice approach.
Thanks very much.