DR-110 DIN SYNCH MOD
By: David Terrill (AlphA)
alphadog303@hotmail.com
http://geocities.datacellar.net/researchtriangle/9730
REQUIREMENTS:
1/8" CLOSED CIRCUIT TYPE phone jack
1/8" phone jack (any)
thin, insulated wire
cable with 1/8" plugs (mono)
electrical tape
soldering iron + solder
5 pin DIN jack
resistors
74HCT74 dual d-type flip-flop with set and reset; positive-edge trigger
PC board
enclosure of your choice
Boss DR-110 Dr. Rhythm GRAPHIC
Some guts
First, remove the 4 knobs from the front and the 3 screws on the back and open the 110 like a book. A ribbon cable at the top holds the two halves together. Careful not to loose the blue power switch cap. The top half is the CPU (digital) board where the internal sequencer is located. The bottom half is the voicing (analog) board where the internal tempo clock is found. You want to disconnect the clock from the sequencer via the ribbon cable. The clock pulses are found on conductor 4. Thinking of the leftmost conductor as 1 the clock pulses are found on the fourth one in from the left. You could disconnect this a number of ways. I found it easiest to cut along both ends of the conductor, vertically, and pull it slightly away from the others, toward me. Then cut it at mid-point. Strip and tin both ends. Solder thin, insulated wires to each end. Insulate the connections with electrical tape. Take the 2 wires and attach them to the 1/8" closed circuit type jack as shown in the schematics. To ground the third lug, I simply used the (-) battery conductor. When finished, check everything out. With nothing inserted into the jack, the 110 should function as usual. After inserting a plug and hitting START the 110 should do nothing. This is because you have bypassed the internal clock with the plug. If your 110 starts playing the pattern at random tempos, don't be alarmed. The sequencer is probably interpreting random static as clock pulses due to the free plug on the other end of the cable. This will not happen once it has been connected to the clock converter circuit you will build externally. Try touching the tip of the plug and it should stop. If all is okay, it's time to build the external clock conversion circuit.
VCC is whatever voltage you are using to power the synch converter. I have been successful with several AC adapters at 4.5 and 9 VDC. I have also used a 9VDC cell. Basically, all you need to do is power the 74HTC74 any way you can. If you can get about 5VDC to pins 4 and 14 you're good. It could probably be powered from the 110 itself but I haven't tried this, for I like to keep my mods as external as possible as not to change the units original look and functionality. The schematics show that the only work I did inside the 110 was to bypass the internal clock. My 110 functions exactly the way it originally did, without the mod, when nothing is connected to it. The only physical change is that it now has a small 1/8" jack on the left side.
The idea behind how this mod works is simple. You are temporarily disconnecting the 110 internal sequencer from it's internal clock and replacing the clock with DIN SYNC pulses. DIN SYNCH runs at 24 pulses per quarter note while the DR-110's internal sequencer runs at 12 pulses per quarter note so this must be converted. The converter is a simple divide by 2 circuit. It spits out 1 pulse for every two it receives. The start/stop pulse is used to reset the 74HCT74 and either allows the pulses to reach the output or stops them. That way, when you start and stop your master DIN driver the 110 also starts and stops. However the 110 must be initialized and reset manually (explained below).
Using the 110 with this mod is simple and flexible. If you followed the schematics and added the mod the way I did you have a 1/8"jack on the left side. This jack is used the feed the internal sequencer clock pulses and also functions as a switch between internal and external clocks. When nothing is inserted, the 110 functions exactly the way it did before the mod. When a plug is inserted, the internal clock is disconnected and replaced with the pulses from the plug.
After you have added the mod, hook it up to the 110 and your master DIN driver (sequencer, another drum machine, etc...). Hit START on the 110. If the unit you are using to drive the 110 is in STOP mode, the 110 will do nothing and wait for clock pulses. This is what I meant by initializing the 110. Then, when you hit START on the driver (master DIN clock), the 110 will start playing in synch with it. You can have it in whatever mode you want (patt play, song play, tap write, even song and step write although the last 2 don't serve much purpose). The 110 is locked in synch but not locked into playing. You can hit STOP and START any time you wish, on the fly. However, the only way to ensure a solid synch is to have everything in STOP mode, hit START on the 110 and then hit START on your master. Also, every time you hit stop on your master, I recommend hitting STOP and then START on the 110. This is the manual reset I mentioned earlier. This ensures that count 1 on your external equals count 1 on the 110. Without hitting STOP and START on the 110, the master would start at the beginning, as usual, and the 110 would start wherever it left off, as if hitting CONTINUE on similar DIN SYNCH machines. The 110 would still be in synch, but off timing.
I was thinking about patching the START/STOP pulses to the 110 so that it automatically locks, but I like having the ability to START,STOP and change modes on the fly. Besides, there isn't much room inside the 110. That 1/8" jack barely has space. That's why I made the mod external (didn't have a choice). You could fit the mod in where the 4 AA batteries are located, and power the mod off of the 110 itself while using the AC adapter thus defeating any reason to have an external device. But, I love using the batteries and playing my 110 on the go.
FUTURE:
While tinkering around with the DR-110's innards and schematics (thanks 110 page) I have located the trigger points for all six sounds. I believe they were negative going. I was also able to edit some of the sound parameters by tapping cretin points with resistance. For example, I could make the CYMBAL sustain indefinitely (no decay). I was tempted to add trigger in's but it's pointless since my 110 synchs to DIN now. I would like to add sound parameters but I don't know where I'd fit them. Any ideas? I would probably have the loose the enclosure and I'm not willing to do that. I don't want to do any more drilling either. I was hesitant just adding the 1/8" jack (glad I did though!).
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Enjoy! Good luck and happy hacking!
Any questions or comments to...
alphadog303@hotmail.com
http://geocities.datacellar.net/researchtriangle/9730
You MUST visit the DR-110 page!!! Go to my links NOW!
NEW!!!
This is the E-mail that I have sent out to everyone that has inquired about this mod.
Hello I have received several inquiries about my 110 sync mod. I even had a few requests to install the mod for some dr-110 owners and said that I would write back when I freed up some of my time. If you are one of those people or you would like the mod installed, I will start doing them now. The cost is $35. If you agree with the terms below, please e-mail me and we can set something up. Many possible methods exist to mod the 110 and this is what I think produces the best results. So, this is how I plan on doing the mod. 1.> You should be willing to use an AC adapter for your power supply. That is what I use for mine and it has been proven to be very reliable and you can pick them up anywhere. Your plug for this should be a 5.0mm with the positive in the center and produce around 4.5 through 9 Volts DC. Mine has been successfully tested with... 4.5VDC 6VDC 7.5VDC 9VDC 12VDC I wouldn't recommend using 12VDC, for the converter circuit is not designed for that. Strangely it works anyway but it would probably cause problems in extended use. Keep it as close to 5VDC as possible. I have been using 4.5VDC . 2.> You will connect the external mod box with a patch cable with mono 1/8" plugs (male) on both ends. So the route will be... [MASTER CLOCK]----din-cable----[110 mod box]----1/8"-cable----[DR110] 3.> You pay the S/H. Obvious reasons. Procedure: *E-mail me and let me know that you are interested in having me install the 110 synch mod into your dr110. alphadog303@hotmail.com *I will reply and let you know when I am ready to receive your dr110 (incase I'm working on someone elses dr110 at the time. *Send your dr110 to the address I give you via E-mail. *it should take no longer than a day or two at most to complete the mod. *I'll E-mail you when testing the mod has proven to be successful (when your dr110 is singing along with my gear). I'll also let you know when I'll be sending it back to you (most likely the next day) with a C.O.D. for 35$+S/H. *You receive your dr110 with a small 1/8" jack mounded on the left side . A small black 3.2" X 2.1" X 1.4" box sporting two DIN jacks, a 5.0mm power jack and a 1/8" jack. Both DIN jacks are DIN SYNC IN/THROUGH. I am not married to this procedure. I just wanted to come up with a method to keep things simple. I'm open to suggentions and adjustments. Thank you for your interest. David Terrill