simple messages filtering : help for asm coding

MIOS programming (Assembler)
1

Hi,

I’m starting a new project with midibox. The goal is to filter incoming midi messages. some mesages i want to convert, some other to block.

I have a Boss midi pedal controller sending only “program change” messages.

I want to play a sample when pressing a pedal, but my sampler need “note on/off” messages.

So the midibox is placed between pedalboard and sampler and needs to convert/filter the messages following a precise table.

The Core V3 pcb is now built, PIC18f452 burnt with bootloader v1.2, then succesfully updated with MIOS v1.9.

I also uploaded the “change_id_v1_9c.zip” troubleshooting app to confirm MIOS is up and running, and application upload also.

In midiox, i receive a correct CC message “0427” saying All is good !

Now i’m writing code in MPLAB, compilation goes well, but my code is ineficient due to my lack of knowledge in programming. I’d prefer to use assembler because my pc is ready to go with it. I haven’t installed the necessary softwares to program in C.

So i’m asking for your help here with those questions :

  1. Where do i need to put my code for filtering ?

(in main.asm in “Notify_Received event” section ?)

  1. do i need to do “addlw 0x07” before reading or writing any byte ?

  2. is it necessary to use “MIOS_begin_stream” ?

  3. How to send a complete midi event ?

  4. Here is the table of conversion i want to apply

IN : incoming messages to midibox (from pedalboard) in hexa

OUT : message to be transmited (or not) when corresponding message is received

IN hex	OUT hex ACTION
-----------------------------------	
PC00	NoteOn24	CONVERT
PC01	NoteOn25	CONVERT
PC02	NoteOn26	CONVERT
PC03	NoteOn27	CONVERT
PC04	X ALL NOTE OFF
PC05	NoteOn29	CONVERT
PC06	NoteOn2A	CONVERT
PC07	NoteOn2B	CONVERT
PC08	NoteOn2C	CONVERT
PC09	X ALL NOTE OFF
PC0A	X BLOCK
PC0B	X BLOCK
PC0C	X BLOCK
PC0D	XX BLOCK
PC0E	X BLOCK
PC0F	X BLOCK
PC10	PC11 PASS
PC11	PC12 PASS
PC12	PC13 PASS
PC13	X BLOCK
PC14	PC15 PASS
PC15	PC16 PASS
PC16	PC17 PASS
PC17	PC18 PASS
PC18	X BLOCK
PC19	PC1A PASS
PC1A	X BLOCK
PC1B	X BLOCK
PC1C	X BLOCK
...	X BLOCK
...	X BLOCK
...	... ...

I’m looking forward to your help, so it could help me make a first step into MIOS programming for next applications.

thank you, RAPHAEL.

2

hi

I probubly I have a bad style of writing app in assembler , but sometimes it work.

If you want - you can check this.

USER_MPROC_NotifyReceivedEvent	movf	MIOS_PARAMETER1, W
	xorlw	0xc0                        ; catch program change on channel 1
	bz	PRG_CH1
return

PRG_CH1                                  ; procedure for assign job for every number
	movf	MIOS_PARAMETER2, W
	JUMPTABLE_2BYTES 32
	rgoto	PC_0
	rgoto	PC_1
	rgoto	PC_2
 ;      ......    here you must fill it yourself

	rgoto	PC_1e
        rgoto	PC_1f

return

PC_0    ;here you can out procedure for PC_0  
	call	MIOS_MIDI_BeginStream
	movlw	0x90                                ;noteon channel 1
	call	MIOS_MIDI_TxBufferPut
	movlw	0x24                                ;like you wanted 24
	call	MIOS_MIDI_TxBufferPut
	movlw	0x7f                                  ; you not said about velocity - so I put maximum
	call	MIOS_MIDI_TxBufferPut
	call	MIOS_MIDI_EndStream
return

PC_1    ;here you can out procedure for PC_1


return

PC_2    ;here you can out procedure for PC_2


return
;...........please write nexts PCn

PC_1f

return

I hope it will help.

3

Hi,

I like your style of writing code ! it makes all things logical to me.

Now the code is like a rolling stone, thanks to you i’ve been able to have the filter running  ;D

Messages are filtered the good way (note on transformation), or blocked correctly.

But “passing” messages does twice  ???

1/

the procedure “PC_PASS” takes all three byte from 1 to 3 and calls MIOS_MIDI_TxBufferPut each time.

Any idea why the message comes twice in the midiox input monitor ?

2/

You create a table called by : “JUMPTABLE_2BYTES 32”

can i make this table 128 x 2BYTES long instead of 32 ?

this is because program changes greater than 1F are converted into notes like procedure PC_0. I don’t see where is the default point of jump/goto…

I would like (ALL PC > 1f) branch to PC_BLOK

I can’t enough say you how much i’m happy this thing is already running tonight. Merci !!!

RaF

[main.asm](< base_url >/applications/core/interface/file/attachment.php?id=3127)

4

hi

I`m happy!

2/

You create a table called by : “JUMPTABLE_2BYTES 32”

can i make this table 128 x 2BYTES long instead of 32 ?

I don`t know. You can check this, but if you need no more than 32 , and want avoid jump over 32 you can read in macros.h file:

JUMPTABLE_2BYTES MACRO max_value

addlw -max_value ; ensure that jump index is not greater than (max_value-1)

skpnc

movlw -max_value

addlw max_value

call MIOS_HLP_GetIndex_2bytes

ENDM

that protection is alerady done. Have you any troubles with value bigger than 32?

I don’t see where is the default point of jump/goto…

sorry I don`t understand, what you mean?

I would like (ALL PC > 1f) branch to PC_BLOK

USER_MPROC_NotifyReceivedEvent	movf	MIOS_PARAMETER1, W
	xorlw	0xc0                        ; catch program change on channel 1
	bz	PRG_CH1
return

PRG_CH1                                          ; procedure for assign job for every number
        movlw 0x20
      CPFSLT MIOS_PARAMETER2	    ;Compare f with W, skip if f < W
      rgoto	PC_BLOCK

        movf	MIOS_PARAMETER2, W
	JUMPTABLE_2BYTES 32
	rgoto	PC_0
	rgoto	PC_1
	rgoto	PC_2
 ;      ......    here you must fill it yourself

	rgoto	PC_1e
        rgoto	PC_1f

return

PC_0    ;here you can out procedure for PC_0  
	call	MIOS_MIDI_BeginStream
	movlw	0x90                                ;noteon channel 1
	call	MIOS_MIDI_TxBufferPut
	movlw	0x24                                ;like you wanted 24
	call	MIOS_MIDI_TxBufferPut
	movlw	0x7f                                  ; you not said about velocity - so I put maximum
	call	MIOS_MIDI_TxBufferPut
	call	MIOS_MIDI_EndStream
return

PC_1    ;here you can out procedure for PC_1


return

PC_2    ;here you can out procedure for PC_2


return
;...........please write nexts PCn

PC_1f

return

PC_BLOCK

return

1/

the procedure “PC_PASS” takes all three byte from 1 to 3 and calls MIOS_MIDI_TxBufferPut each time.

Any idea why the message comes twice in the midiox input monitor ?

do you monitor both inputs (from midibox and your pedal-unit)?

5

Hi

2/

You create a table called by : “JUMPTABLE_2BYTES 32”

can i make this table 128 x 2BYTES long instead of 32 ?

I don`t know. You can check this, but if you need no more than 32 , and want avoid jump over 32 you can read in macros.h file:

this trick is to be obsolete with the “CPFSLT MIOS_PARAMETER2” procedure.

This looks like what i need, in 3 lines of code instead of …too much !

Tested successfuly !

I don’t see where is the default point of jump/goto…

sorry I don`t understand, what you mean?

nothing special, bad word using from me.

1/

the procedure “PC_PASS” takes all three byte from 1 to 3 and calls MIOS_MIDI_TxBufferPut each time.

Any idea why the message comes twice in the midiox input monitor ?

do you monitor both inputs (from midibox and your pedal-unit)?

no, I monitor only the input of pc (output of midibox)

I’m doing more tests next tuesday with the pedalboard and sampler, here at home i only have the pc running midiox and Mios Studio. Test messages are generated by midiox keyboard, sent to the filterbox (its little name  :wink: ), and back to midiox input. I took a special attention not to create a loop by unchecking the box saying “automaticallly attach inpuuts to outputs during selection” in midiox.

Raf

attached are 3 shots from the filterbox itself

778filterbox1jpgd7c523dce3efc66830840a9fc8880223
778filterbox1jpgd7c523dce3efc66830840a9fc8880223307×410 15.8 KB

780filterbox2jpg0457f450dea6e68d26e6dfb058020c4c
780filterbox2jpg0457f450dea6e68d26e6dfb058020c4c410×307 14.7 KB

782filterbox3jpgd92834d22279f318c38cc06ead141014
782filterbox3jpgd92834d22279f318c38cc06ead141014410×307 7.99 KB

6

maybe you can run two instances of Mios Studio (great software! I also use it)

In one you send by midi output PC to filterbox , no using here midi input.

And in second instance you can check by monitor midi input what midifilter do with messages.

7

oh yes ! wonderfull we can launch 2 Mios studio at the same time !  :-X

messages PASSED are stil received twice, same result with 2 mios studio and midiox.

...

	rgoto	PC_BLOK	;pc0e
	rgoto	PC_BLOK	;pc0f
	rgoto	PC_PASS	;pc10
	rgoto	PC_PASS ;pc11
	rgoto	PC_PASS ;pc12
	rgoto	PC_BLOK	;pc13
	rgoto	PC_PASS ;pc14
	rgoto	PC_PASS ;pc15
	rgoto	PC_PASS ;pc16
	rgoto	PC_PASS ;pc17
	rgoto	PC_BLOK	;pc18
	rgoto	PC_PASS ;pc19
	rgoto	PC_BLOK
	rgoto	PC_BLOK

...

PC_PASS    ;procedure for PC_xx : PASS
	call	MIOS_MIDI_BeginStream
	movf	MIOS_PARAMETER1, W ;passe le parametre 1
	call	MIOS_MIDI_TxBufferPut
	movf	MIOS_PARAMETER2, W ;passe le parametre 2
	call	MIOS_MIDI_TxBufferPut
	movf	MIOS_PARAMETER3, W ;passe le parametre 3
	call	MIOS_MIDI_TxBufferPut
	call	MIOS_MIDI_EndStream
	return

looks all good, isn’t it ?

(idiot idea:) i send with parameter 1 then two then 3, or maybe i should reverse the order ?

8

hello,

yesterday i successfully tested the “filter box” with the pedalboard and sampler, all is working good !

Even with the filterbox sending the PC twice, wich not a real problem in action.

So id decided to go on step further, and add a 7 segment LED display to have a visual feedback of selected patch. So before i ask you questions, i will look around code examples and try to create it myslef.

thanks for your contribution QBAS, and to TK for this great project !

RAF

9

you welcome

if you would like you can attach ziped aplication and I can check this on my midibox.

10

about your code

...

	rgoto	PC_BLOK	;pc0e
	rgoto	PC_BLOK	;pc0f
	rgoto	PC_PASS	;pc10
	rgoto	PC_PASS ;pc11
	rgoto	PC_PASS ;pc12
	rgoto	PC_BLOK	;pc13
	rgoto	PC_PASS ;pc14
	rgoto	PC_PASS ;pc15
	rgoto	PC_PASS ;pc16
	rgoto	PC_PASS ;pc17
	rgoto	PC_BLOK	;pc18
	rgoto	PC_PASS ;pc19
	rgoto	PC_BLOK
	rgoto	PC_BLOK

...

PC_PASS    ;procedure for PC_xx : PASS
	call	MIOS_MIDI_BeginStream
	movf	MIOS_PARAMETER1, W ;passe le parametre 1
	call	MIOS_MIDI_TxBufferPut
	movf	MIOS_PARAMETER2, W ;passe le parametre 2
	call	MIOS_MIDI_TxBufferPut
	movf	MIOS_PARAMETER3, W ;passe le parametre 3
	call	MIOS_MIDI_TxBufferPut
	call	MIOS_MIDI_EndStream
	return

can you chane this that please not send all 3 values in case of Program Change, becouse Program change consist from only two parameters, so probubly it is reason why you have a doubled message.

For ezgample Program change #5 on channel 8   

        call        MIOS_MIDI_BeginStream

        movlw        0xc7

        call        MIOS_MIDI_TxBufferPut

movlw      0x05

        call        MIOS_MIDI_TxBufferPut

        call        MIOS_MIDI_EndStream