Starting to use SpinCAD again

[Digital Larry]

You might think that I spend every waking moment.  Well, I used to, but that was about 8 years ago now.

I'm revising my bedroom setup.  I have a Zoom MS50-G that is going to move into the studio, and it feels really weird to play with NO reverb or delay at all.  I am using a Hotone Mojo Diamond which has an FX loop but nothing built-in.  Then I remembered I got this FV-1 pedal from this guy called "Ice-9" which I'd put some experimental tremolo patches in 5 years ago and then forgot about.  But this is really all I need here.

My patches are, so far, some reverbs, an MN3011 sort of reverb, a delay with chorusing on it, and a tremolo/reverb.  Nothing really groundbreaking at the moment.  I like putting a high pass in the delay feedback loop and I also like putting a smoother on the delay time to get that beyooowwww pitch bend when you twist the knob.

Don't know if any of you have ever listened to Mary Halvorson.  She is an avant-garde jazz guitarist who plays through a Line 6 delay with two expression pedals.  The result is something I really never thought I'd hear anyone do, basically it sounds like an off-center vinyl LP with unexpected glitches and pitch wobbles.  I'd categorize it as "interesting" over "enjoyable" but there again, I have listened to a fair amount of it while scratching my head.  I might try something like that, random pitch wobbles.  Yummy!

I'm using it on a Macbook which I never really did before.  I managed to crash it already once and make the sound generation lock up too!  Maybe I'll run it in debug mode like I told that other guy to do to see if I can tell what the problem is.  MAYBE if I get a wild hair (it happens sometimes) I might even fix some bugs.   

DL

[Vivek]

Looking forward to your next innovations, Larry !

[Ice-9]

Then I remembered I got this FV-1 pedal from this guy called "Ice-9" which I'd put some experimental tremolo patches in 5 years ago and then forgot about. 

DL

Hah ! I'm still here dude, glad you have put some use to the project FV-1 pedal, I have been nworking mostly with FXcore DSP for a while now although I do get back to coding for the FV-1 sometimes  (Stanley-FX).

[Digital Larry]

Then I remembered I got this FV-1 pedal from this guy called "Ice-9" which I'd put some experimental tremolo patches in 5 years ago and then forgot about. 

DL

Hah ! I'm still here dude, glad you have put some use to the project FV-1 pedal, I have been nworking mostly with FXcore DSP for a while now although I do get back to coding for the FV-1 sometimes  (Stanley-FX).

Glad to hear it.  Once I decided that I do not have the mindset to actually run a business I shifted away from the FV-1 and never even looked at the FXCore beyond determining that its instruction set was not adequately compatible with the FV-1 to allow easy adaptation from SpinCAD.  If someone else wanted to do that I'd chime in from the sidelines.  I even offered to do it for some large amount of cash but that offer was ignored, which is fine.

I'm still frustrated by the limitations and approach of commercial multi-FX, yet am also hesitant to dive into things like a Mod Dwarf or Peego.  If they were half the price, maybe.  There's a research project under FAUST that's implementing FAUST support on FPGAs.  At the moment the OS is bare metal, so there's not support for something like OSC, which is a shame.  I want something pedal sized that can support OSC.  Still not there!

[Digital Larry]

OK well I busted out the PICKit 2 clone I had and although I was able to read the EEPROM from Ice-9's board I could not write to it over I2C.  Might be a connector or cable problem.  I got my own pedal which I made even though it's a bit on the funky side (no bypass switch, input is on the left and output is on the right) and just swapped out the EEPROM which I programmed in the FV-1 dev board.

By the way I have bare PCBs and components to make about 5 or 6 more of these, and I'm never going to do it, so if anyone out there reading this thinks they might want to buy all of that in one fell swoop, make me an offer.  This is minus the FV-1s themselves mind you.  These are 4-layer PCBs.  As you can see it's mostly SMT but there's some through hole.  The SOT-25 voltage regulator is the hardest thing to solder.

One of the outputs goes to a transistor and with clever programming you can make the blue LED throb with the LFO.

The other cool thing about this design is that there are jacks for regular TRS expression pedals on the back, so all of the knobs can be modified by a pedal.







My first set of programs from SpinCAD wasn't bad!  I'll tweak them up a bit then post them here.  I forgot how amazing it is to use, if I had had to program all those in Spin ASM it would have taken a week.  I knocked it out in about 30 minutes.   

DL

[Ice-9]

I'm not sure why your Pickit2 can only read the eeprom and not program the eeprom via I2C . Maybe check the eeprom write protect pin is connected to gnd rather than 3.3v.

[niektb]

[...]
There's a research project under FAUST that's implementing FAUST support on FPGAs.  At the moment the OS is bare metal, so there's not support for something like OSC, which is a shame.  I want something pedal sized that can support OSC.  Still not there!

I'm almost done with the Teensy Faust layout so if you have a little patience (I know, progress has been a bit slow for me last months  )

[Digital Larry]

I'm not sure why your Pickit2 can only read the eeprom and not program the eeprom via I2C . Maybe check the eeprom write protect pin is connected to gnd rather than 3.3v.

I've definitely programmed this thing with I2C before.  The exact same setup (AFAICT).  Will put it on the scope to see what Mr. Voltage says.

[Digital Larry]

I'm almost done with the Teensy Faust layout so if you have a little patience (I know, progress has been a bit slow for me last months  )

I'm interested.  More info somewhere?  I never tried Faust on a Teensy.  My biggest concern is how quickly one runs out of either code space or delay RAM or execution cycles.  I was all hot thinking the ESP32 was going to be better than an FV-1, but... it wasn't.

[niektb]

[...]

I'm interested.  More info somewhere?  I never tried Faust on a Teensy.  My biggest concern is how quickly one runs out of either code space or delay RAM or execution cycles.  I was all hot thinking the ESP32 was going to be better than an FV-1, but... it wasn't.

You probably already have seen my hardware schematic: https://www.diystompboxes.com/smfforum/index.php?topic=127859.msg1246062#msg1246062
And the documentation on the official website: https://faustdoc.grame.fr/tutorials/teensy/

Not sure what you're shooting for in terms of cpu performance but you can easily tuck some external RAM or external Flash to it if you want to extend it. I've seen people use it for wavetable synthesis by stuffing WAVs on a SD card:  https://www.youtube.com/watch?v=B_KyNA13FWU&t=135s&ab_channel=nanopolis

Fun addition is that it also has native USB-Audio and native USB-MIDI

[Vivek]

I'm so inspired by you Gurus !

I'm new to all of this so I won't have any thing intelligent to add,


But will be on the side lines, cheering !

PS : I tried to put a X100 into an FV-1 with SpinCAD and found that it won't fit.

So next we are trying to keep compressor and distortion as analog, while FV-1 takes over effects duties.

[Digital Larry]

PS : I tried to put a X100 into an FV-1 with SpinCAD and found that it won't fit.

I kinda wondered about that but am not surprised.

[Digital Larry]

I'm not sure why your Pickit2 can only read the eeprom and not program the eeprom via I2C . Maybe check the eeprom write protect pin is connected to gnd rather than 3.3v.

Hi Mick,  looks like the secret is to keep the pedal powered on while trying to program it.  Worked like a charm then!  Good thing too, as your pedal doesn't have the foibles that mine does.  Mine also is suffering from occasional startup problems, as I read millions of such posts on the Spin forum, due to poorly chosen xtal load cap value.  At this stage of my life I'm almost ready to submit to voluntary dental work before doing SMT desoldering.

DL

[Ice-9]

I'm not sure why your Pickit2 can only read the eeprom and not program the eeprom via I2C . Maybe check the eeprom write protect pin is connected to gnd rather than 3.3v.

Hi Mick,  looks like the secret is to keep the pedal powered on while trying to program it.  Worked like a charm then!  Good thing too, as your pedal doesn't have the foibles that mine does.  Mine also is suffering from occasional startup problems, as I read millions of such posts on the Spin forum, due to poorly chosen xtal load cap value.  At this stage of my life I'm almost ready to submit to voluntary dental work before doing SMT desoldering.

DL

That's good news that you got the EEPROM programmed, I can't remember which pcb revision you had, the early forum project PCB would program with no power connected but the Goldmine reverb revision was a bit picky and needed the 9v power connected. I think it could also be a detection thing with the Pickit2 software as the software detects if the board is powered or is to take power from the Pickit. I am unsure if the clone Pickits work the same way.

I was one of the people to discover the FV-1 xtal boot up issues with often resulted in either the xtal not starting at all or a harmonic screatch at startup. I found that every xtal I use a 33pf cap would resolve all problems.

My eyesight is getting a bit knackered now but I still prefer SMD, I would also rather sumit to voluntary dental work than go back to through hole components. Repair work is just so much easier with SMD. (less fear of lifting pads and traces).  

Glad you got up and running again.

[Digital Larry]

Here's one of my first programs.  Nothing too elaborate, a simple tremolo/reverb.  Oooh, this one has the bugs where pot1 and pot2 are hardwired in the ROM Reverb 1 block!  Well it works anyway!  (weird)

Code Select Expand


; Untitled
; Patch saved from SpinCAD Designer version 1023
; Pot 0: Tremolo LFO speed
; Pot 1: Tremolo LFO depth
; Pot 2: Reverb mix
;
;
; ----------------------------
;------ Input
;------ Pot 2
;------ Pot 0
;------ Pot 1
;------ Scale/Offset
RDAX POT2,1.0000000000
SOF 0.8500000000,0.1500000000
WRAX REG0,0.0000000000
;------ Scale/Offset
RDAX POT0,1.0000000000
SOF 0.6100000000,0.3900000000
WRAX REG1,0.0000000000
;------ LFO 1
SKP RUN ,1
WLDS 1,218,32767
RDAX REG1,0.4266144814
WRAX SIN1_RATE,0.0000000000
CHO RDAL,1
SOF 0.5000000000,0.5000000000
WRAX REG2,0.0000000000
;------ Power
RDAX POT1,1.0000000000
;------ ---Invert
SOF -0.9990234375,0.9990234375
WRAX REG3,1.0000000000
MULX REG3
MULX REG3
MULX REG3
MULX REG3
;------ ---Flip
SOF -0.9990234375,0.9990234375
WRAX REG4,0.0000000000
;------ Tremolizer
RDAX REG2,0.9400000000
MULX REG4
SOF -0.9990000000,0.9990000000
WRAX REG5,0.0000000000
;------ Volume
RDAX ADCL,1.0000000000
MULX REG5
WRAX REG6,0.0000000000
;------ ROM_Reverb_1
SKP RUN ,1
WLDS 0,12,160
CHO RDA,0,REG | COMPC,2556
CHO RDA,0,0,2557
WRA 2606,0.0
CHO RDA,0,COS  | REG | COMPC,8348
CHO RDA,0,COS ,8349
WRA 8398,0.0
SOF 0.0000000000,0.7600000000
WRAX REG12,0.0000000000
RDAX POT1,1.0000000000
SOF 0.8000000000,-0.8000000000
WRAX REG13,0.0000000000
RDAX POT2,1.0000000000
SOF 0.8000000000,-0.8000000000
WRAX REG14,0.0000000000
RDAX REG6,1.0000000000
RDA 1399,-0.59
WRAP 1243,0.59
RDA 1623,-0.59
WRAP 1400,0.59
RDA 1956,-0.59
WRAP 1624,0.59
RDA 2505,-0.59
WRAP 1957,0.59
WRAX REG15,0.0000000000
RDAX REG6,1.0000000000
RDA 186,-0.59
WRAP 0,0.59
RDA 440,-0.59
WRAP 187,0.59
RDA 743,-0.59
WRAP 441,0.59
RDA 1242,-0.59
WRAP 744,0.59
WRAX REG17,0.0000000000
RDA 22566,1.0
MULX REG12
RDAX REG15,1.0000000000
RDA 9880,-0.58
WRAP 8298,0.58
RDA 11862,-0.58
WRAP 9881,0.58
WRAX REG11,1.0000000000
RDFX REG7,0.3426232845
WRHX REG7,-1.0000000000
MULX REG13
RDAX REG11,1.0000000000
WRAX REG11,1.0000000000
RDFX REG8,0.0147741276
WRLX REG8,-1.0000000000
MULX REG14
RDAX REG11,1.0000000000
WRA 14521,0.0
RDA 17997,1.0
MULX REG12
RDA 13137,-0.58
WRAP 11863,0.58
RDA 14520,-0.58
WRAP 13138,0.58
WRAX REG11,1.0000000000
RDFX REG9,0.3426232845
WRHX REG9,-1.0000000000
MULX REG13
RDAX REG11,1.0000000000
WRAX REG11,1.0000000000
RDFX REG10,0.0147741276
WRLX REG10,-1.0000000000
MULX REG14
RDAX REG11,1.0000000000
WRA 17998,0.0
RDA 17721,1.0
RDA 22014,0.8
WRAX REG16,0.0000000000
;------ Mixer 2:1
RDAX REG6,1.0000000000
WRAX REG17,0.0000000000
RDAX REG16,0.5011872336
MULX REG0
RDAX REG17,1.0000000000
WRAX REG17,0.0000000000
;------ Output
RDAX REG17,1.0000000000
RDAX REG17,1.0000000000
WRAX DACL,1.0000000000
WRAX DACR,0.0000000000



[potul]

Oooh, this one has the bugs where pot1 and pot2 are hardwired in the ROM Reverb 1 block!  Well it works anyway!  (weird)

I stumbled across this bug of the ROM reverb 1 block only two weeks ago. I forgot to report it, sorry.

[Digital Larry]

Oooh, this one has the bugs where pot1 and pot2 are hardwired in the ROM Reverb 1 block!  Well it works anyway!  (weird)

I stumbled across this bug of the ROM reverb 1 block only two weeks ago. I forgot to report it, sorry.

Hey!  No worries, I already had noted it over at Github.  I'm trying to get spun up again (haha) to do a little work on SpinCAD.  Unfortunately the Xtext/Eclipse development environment has had some breaking changes along the way, so in order for me to even get to where I can build it, it's going to take some effort.

[Digital Larry]

Here's a patch that's kinda like a harmonic tremolo.  Or maybe it just is one, but it's built around a single state variable filter with an oscillating crossfade between the LP and HP outputs.  It's got a fixed reverb because I wanted to devote all 3 knobs to the trem, maybe I'll find a way to combine them somehow.

Enjoy,

DL

Code Select Expand


; Harmonic Trem
; Patch saved from SpinCAD Designer version 1023
; Pot 0: Filter frequency offset
; Pot 1: LFO width
; Pot 2: LFO rate
; Sounds a bit like a harmonic tremolo
;
; ----------------------------
;------ Input
;------ Pot 2
;------ Pot 0
;------ Pot 1
;------ Scale/Offset
RDAX POT0,1.0000000000
SOF 0.3200000000,0.6800000000
WRAX REG0,0.0000000000
;------ Scale/Offset
RDAX POT2,1.0000000000
SOF 0.6100000000,0.3900000000
WRAX REG1,0.0000000000
;------ LFO 0
SKP RUN ,1
WLDS 0,218,32767
RDAX REG1,0.4266144814
WRAX SIN0_RATE,0.0000000000
CHO RDAL,0
WRAX REG2,0.0000000000
CHO RDAL,8
WRAX REG3,0.0000000000
;------ SVF 2 Pole
CLR
RDAX REG5,0.2762733440
MULX REG0
RDAX REG6,1.0000000000
WRAX REG7,1.0000000000
WRAX REG6,-1.0000000000
RDAX REG5,-0.0452652544
RDAX ADCL,1.0000000000
WRAX REG8,0.2762733440
MULX REG0
RDAX REG5,1.0000000000
WRAX REG5,0.0000000000
;------ Power
RDAX POT1,1.0000000000
;------ ---Invert
SOF -0.9990234375,0.9990234375
WRAX REG10,1.0000000000
MULX REG10
;------ ---Flip
SOF -0.9990234375,0.9990234375
WRAX REG11,0.0000000000
;------ Multiply
RDAX REG3,1.0000000000
MULX REG11
WRAX REG12,0.0000000000
;------ Scale/Offset
RDAX REG12,1.0000000000
SOF 0.5000000000,0.5000000000
WRAX REG13,0.0000000000
;------ Crossfade 2
RDAX REG13,-1.0000000000
SOF -2.0000000000,0.0000000000
MULX REG8
WRAX REG15,0.0000000000
RDAX REG13,1.0000000000
SOF 1.0000000000,-1.0000000000
SOF -2.0000000000,0.0000000000
MULX REG7
RDAX REG15,1.0000000000
WRAX REG14,0.0000000000
;------ Reverb
SOF 0.0000000000,0.8500000000
WRAX REG19,0.0000000000
RDAX REG14,0.3548133892
RDA 7260,0.57
WRAP 7104,-0.57
RDA 7484,0.57
WRAP 7261,-0.57
RDA 7817,0.57
WRAP 7485,-0.57
RDA 8266,0.57
WRAP 7818,-0.57
WRAX REG20,0.0000000000
RDA 7103,1.0
MULX REG19
RDAX REG20,1.0000000000
RDA 13826,0.6
WRAP 12244,-0.6
RDA 15808,0.6
WRAP 13827,-0.6
WRAX REG18,1.0000000000
RDFX REG23,0.4000000000
WRLX REG23,-1.0000000000
RDFX REG22,0.0299328144
WRHX REG22,-1.0000000000
RDAX REG18,-1.0000000000
RDAX REG18,1.0000000000
WRA 8267,0.0
RDA 12243,1.0
MULX REG19
RDAX REG20,1.0000000000
RDA 1274,0.6
WRAP 0,-0.6
RDA 2657,0.6
WRAP 1275,-0.6
WRAX REG18,1.0000000000
RDFX REG17,0.4000000000
WRLX REG17,-1.0000000000
RDFX REG16,0.0299328144
WRHX REG16,-1.0000000000
RDAX REG18,-1.0000000000
RDAX REG18,1.0000000000
WRA 2658,0.0
RDA 2658,0.8
RDA 4534,1.5
RDA 10360,1.1
RDA 5451,1.0
WRAX REG21,0.0000000000
SKP RUN ,1
WLDS 1,20,50
CHO RDA,1,REG | COMPC,12294
CHO RDA,1,0,12295
WRA 12344,0.0
CHO RDA,1,COS  | COMPC,50
CHO RDA,1,COS ,51
WRA 100,0.0
;------ Mixer 2:1
RDAX REG14,1.0000000000
RDAX REG21,0.5011872336
WRAX REG24,0.0000000000
;------ Output
RDAX REG24,1.0000000000
RDAX REG24,1.0000000000
WRAX DACL,1.0000000000
WRAX DACR,0.0000000000



[Digital Larry]

All right, I've worked out my build issues and seem to be back in action.  This is something I really never thought I'd do again, but my mind works in strange ways.  Last year I recorded 8 or 10 new tunes.  This year I'm not so lucky but my creative impulses go in different directions.  I found and fixed the ROM Reverb 1 issue.  What now?

[Digital Larry]

OK, here's what I call an "oil-can delay".

The idea is that it's a modulated delay line added to a longer delay line and the period of the LFO matches some multiple of the delay time.  So as feedback comes around then the pitch wobble of the feedback signal is in phase with the next one coming in.  OR IS IT!??!?!?!!  I also put a limiter in the feedback loop which is another trick to allow high levels of feedback without it just blasting into total distorted mush.  I also put an overdrive in front of the delay line, but not inside the feedback loop.  WHICH ISN"T REALISTIC!!!!  So sue me!

Code Select Expand


; Oil Can delay
; Patch saved from SpinCAD Designer version 1029
; Pot 0: Delay Mix
; Pot 1: Feedback
; Pot 2: LFO Rate/Delay Time
;
;
; ----------------------------
;------ Input
;------ Pot 2
;------ Pot 0
;------ Pot 1
;------ Scale/Offset
RDAX POT0,1.0000000000
SOF 0.8500000000,0.1500000000
WRAX REG0,0.0000000000
;------ Smoother
RDAX POT2,1.0000000000
RDFX REG1,0.0001873653
WRAX REG1,0.0000000000
;------ Scale/Offset
RDAX REG1,1.0000000000
SOF -1.0000000000,0.9990000000
WRAX REG2,0.0000000000
;------ Scale/Offset
RDAX REG1,1.0000000000
SOF 0.8000000000,0.2000000000
WRAX REG3,0.0000000000
;------ Scale/Offset
RDAX REG2,1.0000000000
SOF 1.0000000000,0.2000000000
WRAX REG4,0.0000000000
;------ Feedback Output
;------ LFO 0
SKP RUN ,1
WLDS 0,126,12762
RDAX REG4,0.2465753425
WRAX SIN0_RATE,0.0000000000
CHO RDAL,0
SOF 0.5000000000,0.5000000000
WRAX REG6,0.0000000000
;------ Overdrive
RDAX ADCL,1.1300000000
SOF -2.0000000000,0.0000000000
RDAX REG7,0.7000000000
WRAX REG7,1.0000000000
RDAX REG8,-0.3000000000
WRAX REG8,0.2300000000
WRAX REG9,0.0000000000
;------ ThreeTap
RDAX REG5,1.0000000000
MULX POT1
RDAX REG9,1.0000000000
WRA 0,0.0
CLR
OR $007FFF00
MULX REG3
SOF 0.4746520996,0.0250122070
WRAX ADDR_PTR,0.0000000000
RMPA 1.0
WRAX REG10,0.0000000000
;------ Servo Flanger
SKP RUN ,1
WLDR 0, 0, 4096
CLR
RDAX REG10,1.0000000000
WRA 16373,0.0
CHO RDAL,2
RDAX REG6,-0.0800000000
WRAX RMP0_RATE,0.0000000000
CHO RDA,2,REG | COMPC,16373
CHO RDA,2,0,16374
RDFX REG12,0.3239568324
WRLX REG12,-1.0000000000
WRAX REG11,0.0000000000
;------ RMS_Limiter
RDAX REG11,0.5200000000
WRAX REG13,1.0000000000
MULX REG13
WRAX REG17,1.0000000000
RDFX REG14,0.1000000000
WRAX REG14,1.0000000000
LOG -0.5,-0.125
WRAX REG18,1.0000000000
EXP 1.0,0.0
WRAX REG15,1.0000000000
MULX REG11
SOF 1.5000000000,0.0000000000
WRAX REG16,0.0000000000
;------ Mixer 2:1
RDAX ADCL,1.0000000000
WRAX REG19,0.0000000000
RDAX REG11,0.5011872336
MULX REG0
RDAX REG19,1.0000000000
WRAX REG19,0.0000000000
;------ FB In 2
RDAX REG16,1.3400000000
WRAX REG5,0.0000000000
;------ Output
RDAX REG19,1.0000000000
RDAX REG19,1.0000000000
WRAX DACL,1.0000000000
WRAX DACR,0.0000000000