thoughts on Digitech Space Station eprom copying?

[marmaliser]

Really fancy having a go at the fantastic XP All mod. 

Does this PCB look right compared to the perfboard ?

[digi2t]

Looks good to me. I know it's tight for R3, but I would maybe move the pad for pin 3 down some, and move a pad for R3, so I could have the resistor lay down flat (opposite R1). It's impossible to do with perf, and not add another row of holes, but with a PCB, you can extend your trace, and make it work. You won't have one resistor standing up either.

Nice work!

[marmaliser]

Good idea, standy up resistors are the devils work.

Decided to go across the top though.

<images removed>

If this looks right I will send it off to OSHPark

Scratch that R3 across the top and R1 on the left hand side now so all the wires are on the same side and the board is smaller

[digi2t]

Beautiful work! Very nice.

[marmaliser]

Thanks, its my first ever PCB, I will have a spare that you can have for free if you want  as the writer of the most excellent guide.  Or i can share on oshpark if you wanted to order some of your own. $11.50 for 3

Is there anyone in the UK that can Erase then  burn me the XP all + image  ?.  I have the chip

[Govmnt_Lacky]

@marmaliser

I might be interested in one of your boards if you happen to find a spare 

If you cannot find anyone to burn your program.... I might be able to do it for you BUT... I am in the US 

If not, look into the TL866CS programmer on eBay. Its about $30-40 and it works great on the 27C series EPROMS.

Let me know about the board if you find one! 

[marmaliser]

@marmaliser

I might be interested in one of your boards if you happen to find a spare 

If you cannot find anyone to burn your program.... I might be able to do it for you BUT... I am in the US 

If not, look into the TL866CS programmer on eBay. Its about $30-40 and it works great on the 27C series EPROMS.

Let me know about the board if you find one! 

It would be a pleasure to let you have a board (free) as I can see you and dig2t went through a lot to get this working.

[Govmnt_Lacky]

It would be a pleasure to let you have a board (free) as I can see you and dig2t went through a lot to get this working.

I greatly appreciate it sir! I actually "mostly" use the 27C256 chips in my builds BUT, I want to build one for myself and use the 27C1001 for it 

I will PM you my details and you can decide if you want to send over your chip for programming 

[marmaliser]

Finally got a XP100 and I guess I am lucky as it is the version with the SMD chip already on.
I have the adapter board in place and all the sockets just waiting for a few bits now.

Dino do you have an idiots guide for the wiring of the XP ALL+ mod (minus the LED's)  Could really do with this wire goes from here to here etc and the switch poles
Oh and did the boards you ordered work out ?  If I was to do anymore I think I would space things out a bit more and leave enough room for plug connectors to make the wiring a bit easier.

[Govmnt_Lacky]

Dino do you have an idiots guide for the wiring of the XP ALL+ mod (minus the LED's)  Could really do with this wire goes from here to here etc and the switch poles

Gonna try to field this one 

Do you have the most recent build doc? The wiring for the XP ALL+ is in there. Or, do you need something a bit more specific?

[digi2t]

I have to echo G_L on this one. The latest version of the doc has all the wiring drawn out, in the XP-ALL+ section. The only thing that might be a bit vague, is the R30 to relay wiring, but it is shown on the vero layout, a page or two previous. In a nutshell, R30 wires are connected to the N.O. (normally open) side of the relay.

I did get some adapter boards. They're very smart indeed, thanks.

[marmaliser]

No worries, I guess I am just been lazy and a bit blinded by all the wires (never done a rotary switch before)
Once I get soldering I am sure it will become clear

[marmaliser]

First off sorry for double posting but i am wiring up the switch now and it isn't making much sense

I could do with which wire connects to which number terminal on the switch

I have the following wires

U13 (I) goes to ?? switch number
U13 middle leg goes to etc
VSS mod board 
Ground Mod board
A14 Mod board
A15 Mod Board
A16 Mod board
XP100 stereo power relay from Mod board

I am such a noob when it comes to switches. Would really appreciate it if one of you guys could fill in the little table above form..TIA ..M

[digi2t]

OK....

First and foremost, tell me what kind of rotary switch you are using. Post a photo of it as well, if possible. The reason for this request is because the ALPS switches (for example) skip some numbers. I just need to be sure which switch you are using.

Once I have that info, I`ll list each wire, with the corresponding switch deck/pole number.

That`s as easy as I can make it for you... other than you paying me to come to your house. In which case, you better have Cuban cigars and a bottle of 20 year old port on stand-by. 

[marmaliser]

 
Much appreciated

Here is the pic of the switch

Direct link just in case https://www.dropbox.com/s/xuc15g83r8a5h81/switch.jpg

and here is the board just for completeness



https://www.dropbox.com/s/jt0n1jb8xzj20k9/board.jpg

[digi2t]

Damn lad... I was hoping to see a plane ticket instead. Oh well, tie down your tuque with some bailing wire, 'cuz here we go...

First explination of what I mean by switch "decks". Since we have so many contacts, the ALPS switches stack them in decks, so in essence, we have two 3P4T rotary switches, one per deck, in one switch.



Next, we have to determine which are the COMMON terminals, and their correspoding contacts. The COMMON, or COM for short, is the contact that moves when you turn the switch. It will make contact with one of it's contacts in it's group. In this case, since we have four possible positions, we have one COM, and four contacts. On this ALPS switch the COM terminal is denoted by having little "ears" on the tip of the terminal.



In the build doc, the COM is shown as the "finger" of the switch that would move to make contact with the terminals, or "contacts".



On this ALPS switch, the contacts are first, followed by the COM for that section. NOTE THAT SOME OF THE NUMBERS ARE NOT USED, SO IT'S NORMAL THAT NUMBERS MAY BE MISSING IN THE SEQUENCE. If we imagine looking at the switch from the top (shaft) side, the contacts and COM's are laid out as such for one deck. Each deck is identical.



The number 1 contact is where the COM 6 would be, if your selector was turned completely to the left (ccw). Contacts 1, 2, 4, and 5 are served by COM 6. Contacts 7, 8, 10, and 11 are served by COM 12, and so on. So, we have 3 COM's (3P), and 4 contacts (also called "throws") for each COM (4T). Hence, a 3P4T switch. The fact that we have stacked two together, makes this a 6P4T.

In the XP-ALL+, the switch numbers correspond as follows to the connections. Note that everything is numbered in orientation of looking at the switch as you would in reality. Position 1, giving you XP-100 mode, position 2 XP-200, and so on. THE UPPER CONNECTIONS (FOR A14, A15, AND A16) REPRESENT ONE DECK, AND THE LOWER SET, THE OTHER DECK.



I hope that this clarifies the connections where the rotary switch is concerned. As far I can see, connection labels are pretty well covered in the build document. For example "A14" is shown on the prefboard layout as connecting to pin 29, and R1. The wire from the adapter board would connect to terminal 6 on the rotary switch in this case.

With the above info in mind, take the time, and go through it slowly. I'm sure that your brain will have the "Eureka!" moment, and it will all come together for you. If not... I'm on vacation for 4 weeks, end of February, beginning of March. Get the airfare, port, and cigars ready.

[marmaliser]

I AM NOT WORTHY 

Sincere thanks

Eureka moment came with the red numbers on the switch pole diagram.. It had just not sunk in until then

Anyway I know have a pedal that is doing all but the second position (XP200) so I will be checking my adapter board and soldering etc.

[Govmnt_Lacky]

Anyway I know have a pedal that is doing all but the second position (XP200) so I will be checking my adapter board and soldering etc.

Let us know what comes of this!

Was gonna use the adapter board but now... I will hold off until we hear back. 

[digi2t]

I AM NOT WORTHY 

Sincere thanks

Eureka moment came with the red numbers on the switch pole diagram.. It had just not sunk in until then

Anyway I know have a pedal that is doing all but the second position (XP200) so I will be checking my adapter board and soldering etc.

In my book, everybody that tries is worthy. I didn`t get this far by not trying, and asking questions along the way. I`m glad that it helped. It`s always a worry for me when I write stuff up, that what makes sense to me, may not neccessarily make sense to someone else. It always reminds me of Denzel Washington in «Philadelphia» when he says «OK, now explain it to me as if I was a 4 year old».

Anyway I know have a pedal that is doing all but the second position (XP200) so I will be checking my adapter board and soldering etc.

Let us know what comes of this!

Was gonna use the adapter board but now... I will hold off until we hear back. 

Hmmm... I haven`t tried it yet, but it should be pretty easy to validate. Continuity check should take a couple of minutes.

[Govmnt_Lacky]

Hmmm... I haven`t tried it yet, but it should be pretty easy to validate. Continuity check should take a couple of minutes.

YEs but.... I'm LAZY 

And I am battling another monster project right now!