MIDIbox

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This page will contain the information about the combined lcd/button matrix

right now I'm using a modified version of the sm_simple C example but this code will be rewritten to make it more coherent

modifications to scan matrix example:
in main.c:

...
//second shiftregister drives the leds
#define LEDOUT 1
...
void LM_SetRow(){
	MIOS_DOUT_SRSet(LEDOUT,ledtest[sm_col]);
}

/////////////////////////////////////////////////////////////////////////////
// This function is called by MIOS before the shift register are loaded
/////////////////////////////////////////////////////////////////////////////
void SR_Service_Prepare(void) __wparam
{
  // call the Scan Matrix Driver
  SM_PrepareCol();
  // call the Led Matrix Driver
  LM_SetRow();
}
...

in sm_simple.asm:

...
	global	_sm_button_column
	global	_sm_button_row
	global	_sm_button_value
	global  _sm_col

	;; import lables
	extern	_SM_NotifyToggle

; ==========================================================================

accessram		udata		; (no access ram required, these variables can be located anywhere)

_sm_button_column	res	1	; exported to C, therefore an "_" has been added
_sm_button_row		res	1
_sm_button_value	res	1
_sm_col				res 1

...

SM_PrepareCol
	;; select next DOUT register

	;; (current column + 1) & 0x07
	SET_BSR	sm_selected_column
	incf	sm_selected_column, W, BANKED	; (* see note below)
	andlw	0x07
	;_sm_col is used by LM_SetRow()
	movwf	_sm_col
	call	MIOS_HLP_GetBitANDMask	; (inverted 1 of 8 code)
...

and finally in sm_simple.h:

...
extern unsigned char sm_button_value;
extern unsigned char sm_col;
...