Reading Sysex messages from Bankstick

[robinfawell]

Dear Thorsten

I am currently thinking about the next stage in the organ program.

  I need to be able to read the sysex files that are stored on 2 Banksticks.

The information was stored at various starting addresses, previously in assembler using the following code.

;;IN:	Index (Midi_EVNT1 or canc) in WREG
;;OUT: Bankstick Address in MIOS_PARAMETER [12]
;;	Count in TMP [12]
;;	Bankstick # in TMP3

MIDIO_BANKSTICK_DUMP_GET

	Mullw 6 

	;; the addresses jump in increments of 6 bytes 
	;; result of multiplication is in PROD[HL]
	;; Add Offset to base address of table 16 bit addition)
	;; copy result to TBLPTR[HL]
	movlw (BANKSTICK_DUMP_TABLE & 0xFF)
	addwf PRODL, W
	movwf TBLPTRL
	movlw (BANKSTICK_DUMP_TABLE >>8) & 0xFF
	addwfc PRODH, W
	movwf TBLPTRH


;; First Entry: Bankstick Number
	tblrd*+
	movff	TABLAT, TMP3
	;; Second Entry: dummy, not used
	tblrd*+
;; Third & Fourth Entry: Bankstick Address
	tblrd*+
	movff	TABLAT, MIOS_PARAMETER1
	tblrd*+
	movff	TABLAT, MIOS_PARAMETER2

;; Fifth & Sixth Entry; Count
	tblrd*+
	movff	TABLAT, TMP1
	tblrd*+
	movff	TABLAT, TMP2




	movf	TMP3, W
	call	MIOS_BANKSTICK_CtrlSet
	call	MIDIO_SYSEX_Send_Block
	return	

MIDIO_SYSEX_Send_Block
MIDIO_SYSEX_Send_BlockLoop
	clrwdt;; used for Reset large file
	call	MIOS_BANKSTICK_Read ;; Expects Addr in ;;MIOS_PARAMETER[12], Read byte from BS	
	call	MIOS_MIDI_TxBufferPut
	;;Decrement 16 bit loop counter, loop until counter is zero	
	decf	TMP1,	F	
	skpc
	decf TMP2,	F
	bc 	MIDIO_SYSEX_Send_BlockLoop
	return;; This may need changing



BANKSTICK_DUMP_TABLE
;;		BS No  	Addr  	Count
	dw	0x0000,	0x0000,	0x04D4 - 1
	dw	0x0000,	0x04D4,	0x04D4 - 1
	dw	0x0000,	0x09A8,	0x04D4 - 1
	dw	0x0000, 0x0E7C, 0X09A8 - 1
	dw	0x0000, 0x1824, 0X04D4 - 1
	dw	0x0000, 0x1CF8, 0X04D4 - 1
	dw	0x0000, 0x21CC, 0X04D4 - 1
	dw	0x0000, 0x26A0, 0X03C0 - 1	

	dw	0x0000,	0x2A60,	0x04BC - 1
	dw	0x0000,	0x2F1C,	0x04CA - 1
	dw	0x0000,	0x33E6,	0x032C - 1
	dw	0x0000,	0X3712, 0X0000 - 1
	dw	0x0000,	0X3712, 0X0000 - 1
	dw	0x0000,	0X3712, 0X0000 - 1
	dw	0x0000,	0X3712, 0X0000 - 1
	dw	0x0000,	0X3712, 0X0000 - 1

	dw	0x0000,	0x3712,	0x02F4 - 1
	dw	0x0000,	0x3A06,	0x02F4 - 1
	dw	0x0000,	0x3CFA,	0x02F4 - 1
	dw	0x0000,	0x3FEE,	0x01E0 - 1
	dw	0x0000, 0X41CE, 0X0000 - 1
	dw	0x0000, 0X41CE, 0X0000 - 1
	dw	0x0000, 0X41CE, 0X0000 - 1
	dw	0x0000, 0X41CE, 0X0000 - 1

	dw	0x0000,	0x41CE,	0x0574 - 1
	dw	0x0000,	0x4742,	0x028C - 1
	dw	0x0000, 0X49CE, 0X0000 - 1
	dw	0x0000, 0X49CE, 0X0000 - 1
	dw	0x0000, 0X49CE, 0X0000 - 1
	dw	0x0000, 0X49CE, 0X0000 - 1
	dw	0x0000, 0X49CE, 0X0000 - 1
	dw	0x0000, 0X49CE, 0X0000 - 1

	dw	0x0001,	0x0000,	0x04CA - 1
	dw	0x0001,	0x04CA,	0x04CA - 1
	dw	0x0001,	0x0994,	0x04CA - 1
	dw	0x0001,	0x0E5E,	0x04CA - 1
	dw	0x0001,	0x1328,	0x04CA - 1
	dw	0x0001,	0x17F2,	0x04CA - 1
	dw	0x0001,	0x1CBC,	0x032C - 1
	dw	0x0001, 0X1FE8, 0X0000 - 1

	dw	0x0001,	0x1FE8,	0x02F4 - 1
	dw	0x0001,	0x22DC,	0x01E0 - 1
	dw	0x0001, 0X24BC, 0X0000 - 1
	dw	0x0001, 0X24BC, 0X0000 - 1
	dw	0x0001, 0X24BC, 0X0000 - 1
	dw	0x0001, 0X24BC, 0X0000 - 1
	dw	0x0001, 0X24BC, 0X0000 - 1
	dw	0x0001, 0X24BC, 0X0000 - 1

	dw	0x0001,	0x24BC,	0x0574 - 1
	dw	0x0001,	0x2A30,	0x03A0 - 1
	dw	0x0001,	0x2DD0,	0x03A0 - 1
	dw	0x0001,	0x3170,	0x03A0 - 1
	dw	0x0001,	0x3510,	0x03A0 - 1
	dw	0x0001,	0x38B0,	0x0574 - 1
	dw	0x0001,	0x3E24,	0x0574 - 1
	dw	0x0001,	0x4398,	0x028C - 1

	dw	0x0003,	0x0000,	0x4056 - 1
	dw	0x0003,	0x4056,	0x0AC4 - 1
	dw	0x0003,	0x4B1A,	0x0AC4 - 1
	dw	0x0003,	0x55DE,	0x0000 - 1
	dw	0x0003,	0x55DE,	0x0000 - 1
	dw	0x0003, 0x55DE, 0X0000 - 1 
	dw	0x0003,	0x55DE,	0x0000 - 1
	dw	0x0003,	0x55DE,	0x0000 - 1

I assume that using "C", the address and count will be located in an array associated with the" pin" variable.  I may also, I think,  need to include the clwdt in the loop for the large "reset" byte count.

I think that the following is pertinent.

MIOS functions (MIOS_*) can mostly be called from a C program without performance loss, so long it has only one input and/our output parameter. Functions with more parameters require some extra code which copies the C parameters (which are pushed into the stack) to MIOS_PARAMETER[123]

Is it better to have an assembler routine or will the loop program be OK using loops in C program code.

Your help will be appreciated.

Regards Robin

[TK.]

Hi Robin,

it's better to re-write this in C, because this improves the flexibility.

Yes, the long table is just an constant array, all the pointer calculation stuff will be done by the compiler.

In general the code looks like this:

const unsigned int dump_table[] = {
   //  BS    Addr    Count
   0x0000, 0x0000, 0x04d4 - 1,
   0x0000, 0x04d4, 0x04d4 - 1,
   // etc...
};

void SendDump(unsigned char dump_index)
{
  unsigned int addr      = dump_table[dump_index*3 + 1];
  unsigned int count     = dump_table[dump_index*3 + 2];

  MIOS_BANKSTICK_CtrlSet((unsigned char)dump_table[dump_index*3 + 0]);  // converted int -> char

  do {
__asm
    clrwdt
__endasm;
    
    MIOS_MIDI_TxBufferPut(MIOS_BANKSTICK_Read(addr++));
  } while( count-- );
}
[/code]
As you can see, the special clrwdt instruction has to be inserted inside a __asm block
Best Regards, Thorsten.