MIDIbox SID V2 ‘LFO POSITIVE LED’ never lights up

[Oli]

Hi, I'm currently building a MIDIbox SID V2 with the complete Control Surface. Everything works great, except for one thing. The additional ‘LFO POSITIVE LED’ never lights up. I can rule out errors on the hardware side, as I have already assigned ‘TMP5, 5,’ to other DOUTs and the LED does not light up then either. However, other functions are displayed on the outputs without any problems. I have of course already changed the LFO DEPTH and RATE. With positive LFO waveforms, for example, Random + Sine lights up, as described in the manual.

Can anyone tell me what the problem might be or does something else need to be changed in the code?
Thanks!

[Smithy]

Have you used the diode test function with your multimeter to see if the LED illuminates?

First thing I would check is if the anode and cathode are in the correct holes or if the LED is dead. 

Edited July 21 by Smithy

[Oli]

Many thanks for the quick reply.

Yes, I sent another function to this LED as a test and it then worked without any problems. So I can actually rule out everything on the hardware side.

Unfortunately, I can't find many SIDs where the LED is used. I also couldn't find any videos on YouTube where someone has installed this LED and you can see it in use.

In my *.asm file, the DOUT line looks like this (Shift Register 6):

DOUT_ENTRY TMP5, 5,       6, 7             ; LFO Positive LED

Is that all I need to enter for the LED function to work?

[acfnews]

Hi Oli,

 

I just stumbled upon your question, and I never considered this function, however, it might be interesting...

My first question would also be, which of the LFO's would it indicate, as there are 6? Is it a sum? Not sure....

 

As a test I configured my ASM file, and added a line for the function (and removing a working function from the hardware position just like you did).

In my case the first SR1,0 (normally used for SID1 LED indicator).

        DOUT_ENTRY      TMP5, 4,                                0,      0       ; LFO Random LED

        DOUT_ENTRY      TMP5, 5,                                1,      0       ; LFO positive LED


        ;; additional LED functions which could be added:

 

However, on first test, no magic....`

I will also have a look to see if I get thus going in a way...

[Oli]

Hello acfnews,

Thank you for your reply and your test.

I suspect that the LED would indicate the positive range of the currently selected LFO. That would make the most sense to me.
In some pictures and videos, I find SIDs that have this LED installed. But I have not seen it light up in any picture or video.
Perhaps someone who has installed this LED and has it displaying something can say more about it.

If you find out more or get the function to work, please let me know. :-)

Best regards,

Oli

[acfnews]

I just shared this thread in the Discord channel. Maybe that helps. At least there are knowledgable people there :-)

Also tried to find some clues in the code, but this is hard for me.

I did find something interesting (not sure if it is relatated at all), in src/cs_menu_leds.inc
Searching for the word 'TMP5' shows  in line 127: 
 

127         ;; TMP5[5..0]: LFO waveform

and in line 159:

159         ;; TMP5[6]: SID play state

So in this file it looks like it's structured, but is the 'array' [5..0] correct? Should it be [4..0], and should there be a separate section for TMP5[5]?

 

 

[nILS]

From what I gather from the manual and changelog, this LED indicates whether you have selected a „positive values only“ waveform for the LFO (instead of applying the default workaround by showing waveform LED + Random LED).

It does not indicate that the value of the LFO is currently positive.

[Oli]

 

13 hours ago, acfnews said:

I just shared this thread in the Discord channel. Maybe that helps. At least there are knowledgable people there :-)

Also tried to find some clues in the code, but this is hard for me.

I did find something interesting (not sure if it is relatated at all), in src/cs_menu_leds.inc
Searching for the word 'TMP5' shows  in line 127: 
 

127         ;; TMP5[5..0]: LFO waveform

and in line 159:

159         ;; TMP5[6]: SID play state

So in this file it looks like it's structured, but is the 'array' [5..0] correct? Should it be [4..0], and should there be a separate section for TMP5[5]?

 

 

I looked at exactly the same thing and thought the same thing. But since the firmware is relatively old and I couldn't find anyone else whose LED wasn't lighting up during my search, I thought it couldn't be the firmware.

 

11 hours ago, nILS said:

From what I gather from the manual and changelog, this LED indicates whether you have selected a „positive values only“ waveform for the LFO (instead of applying the default workaround by showing waveform LED + Random LED).

It does not indicate that the value of the LFO is currently positive.

That's what I'm thinking too, but where do you turn this feature on? For me, for example, Sine+Random light up at the same time when I have a positive Sine LFO waveform. That's how it's explained in the manual. You should be able to turn off this display feature and turn on the separate LFO positive LED, right?


It is installed in many MB 6582 models. (Picture attached) But when I compare the ASM files, I can't find any differences.

And in this video, you can see at the beginning how the preset is changed and then LFO 1 has a positive triangle waveform. So there, the LFO positive LED lights up instead of the random LED. https://www.youtube.com/watch?v=FA0i5-bAfUQ

 

[acfnews]

I have still exactly the same 'issue'...

From another place in the manual ( LFO section ) http://ucapps.de/midibox_sid_manual_l.html
 

• Wav (Waveform): selects the shape of the LFO. Following waveforms are provided: Sine, Triangle, Pulse, Ramp (Sawtooth), Random (Sample&Hold), and positive Sine/Triangle/Pulse/Ramp

 

So I would indeed expect the 'positive' LED to be lit (new style?), in stead of the multiple leds (old style?) when selecting the other waveforms in the active/selected LFO...

Will be doing some more investigations in the ASM configuration file, as it seems to be another setting :-)

 

 

Edited 3 hours ago by acfnews

[acfnews]

After some digging/debugging, it turns out we need to set the following variable to '1' to have this 5th LED working: 

DEFAULT_MB6582_CS

 

I found this out by this table in src/cs_menu_leds.inc where the fifth bit (reading from right to left) is only set in the first 'if' routine:

CS_MENU_LED_LFO_Wav_Pattern
        andlw   0x0f            ; 16 entries
        JUMPTABLE_2BYTES_UNSECURE
        retlw   b'00000001'     ; Sine
        retlw   b'00000010'     ; Triangle
        retlw   b'00000100'     ; Saw
        retlw   b'00001000'     ; Pulse
        retlw   b'00010000'     ; Random
#if DEFAULT_MB6582_CS
        retlw   b'00100001'     ; Positive Sine
        retlw   b'00100010'     ; Positive Triangle
        retlw   b'00100100'     ; Positive Saw
        retlw   b'00101000'     ; Positive Pulse
#else
        retlw   b'00010001'     ; Positive Sine
        retlw   b'00010010'     ; Positive Triangle
        retlw   b'00010100'     ; Positive Saw
        retlw   b'00011000'     ; Positive Pulse
#endif
        retlw   b'00011111'     ; reserved
        retlw   b'00011111'     ; reserved
        retlw   b'00011111'     ; reserved
        retlw   b'00011111'     ; reserved
        retlw   b'00011111'     ; reserved
        retlw   b'00011111'     ; reserved
        retlw   b'00011111'     ; reserved