Post your questions, opinions and reviews of the MPC1000. This forum is for discussion of the OFFICIAL Akai OS (2.1). If you wish to discuss the JJ OS, please use the dedicated JJ OS forum
By JVC Thu Jan 23, 2020 2:08 pm
Sense-A wrote:The one I installed into my Kurzweil K2000 has a resistor jumping from pin 3 to pin 21. pin 22 is not used.

I looked at the pinout for the linked replacement T6963 and the LCD pinout in the MPC1000 service manual. Most pins appear to match up. However...

The MPC 1000 LCD has 20 pins. The replacement has 22 pins.
Pin 9 from the mpc1000 must go to pin 20 on the T6963. Just how Slump drew it.
Slump left pins 10 disconnected on both sides. I'm not sure if that's okay.
Pin 10 on the T6963 is "Reset Signal" whereas on MPC 1000 it says "PWRGDB"
Also the T6963 has +5V backlight on pin 21 and 0V backlight cathode on pin 22. I'm not sure if these can be left unhooked or not...

Although, I found that if I connected the anode pin (LED_A) and logic power pin (VCC) together on the actual display unit, while also connecting the ground (LED_K) to ground, I could get the backlight to light, but it's generally advised against for reasons I'm not sure of. This Is why I ultimately decided to pull a separate 5v for the LED from the power section of the PCB. The problem is the mpc is so much more complex and I don't know if I have the technical know how to find a clean and easily accessible 5v source just to power the backlight's LED. Again, looking at the mpcstuff.com's product photo I can see that the A and K pins on the board have big globs of hot glue on them. Did they just connect the anode (Pin A) to the logic supply voltage (VCC)? Does it actually matter that much to have a clean independent voltage to power the LED?


On the one for my Kurzweil K2000, I think the guy jumped pin 3 (VCC +5V) to pin 21 as you did. But he used a resistor to make the jump, which probably is there for protection and for the same reason you were advised not to use the single source 5V to power both the VCC and backlight without a resistor.

You can probably leave pin 22 not connected (NC).

Too bad Slump hasn't responded. he seemed to be the furthest along and close to getting it working.



I replaced my K2000 keyboard's LCD display. All I did was remove the old LCD screen and place the new compatible LCD screen, which had 22 pins. The additional 2 pins are for backlight LEDs, which you'd just supply 5V DC from power supply.
As far as all the connection goes, it is that simple. No sane LCD manufactures would change PIN outs! Just connect pin to pin (don't leave any pins unsoldered), and provide 5VDC on Pin 21 & 22.
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By Nick The Slasher McGuirk Wed Feb 05, 2020 10:19 pm
Hi everyone,

I was doing this mod all by my own, and then I found this topic.
I bought ERM24064DNS-1 and then I followed Slump pinout scheme. It toke some time to figure out the pinout on replacement, I'm using single patch cables, the one used with breadbord for temporary circuits. mine pin legs was presoldered facing the back of replacement's display. This give me some trouble to find pin 1. So, If you look to the original display, side by side with mainboard, the pin 1 on display is up, and on the mainboard is down, so the placement is reverse and not really 1to1 to the sight in my case.
Anyway done the pin 9(from manboard) to pin 20(on replacement display) thing. The pin9( on replacement display) can be leaved not connected. The cable that were on pin20 (on replacement display) can be leaved not connected, but I suggest to connect to pin 9, to not leave things messed.
If you done this well, on poweron you see blink screen and orizzontal lines for a sec, and the default lights on unit power up. Else the lights on unit don't power up, so check pinout scheme.
I suggest to check the brightness on poweron, the replacement don't save brightness setting. So everytime, in my case, I need to set brightness with STOP+WHEEL to show characters.
I'm using white on black display, so the first time I was worried I burned everything, but then thinking with cold mind, it was right, with this color scheme the dominant color is black :Sigh: so when power ups it remains black.
So I can confirm the EntonDelMonte replacement display described in 1st post is working with MPC1000, thank also to Slump pinout scheme.

Now I need some help for the backlight. Where is the best place to take 5V for the pin 21 and 22?
I tried to take it from the SDcard, like someone suggested, but I didn't have luck.
I trust in some one can help me about this.

Thankyou very much
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By Nick The Slasher McGuirk Fri Feb 07, 2020 5:03 pm
Hi,

a little update:

I connected pin 21 to pin 2,and 22 to pin 4, on the cable from the front panel, it came straight from the ADDA board. The specs tells it was a 12V. the backlight worked well for an hour, then I had the bad idea to load a project from SD. after full load the project, backlight shut off and ADDA fried.
I can't hear or sample anything from both headphones or back ports.
everything else is working.

can anyone give me a hint to what happened?
By vanwerk Sun May 24, 2020 1:01 am
Hopefully I can put any uncertainty to rest! I successfully installed one of the BuyDisplay LCDs in my MPC1k. As others have pointed out, you will need to swap pins 9 and 20 in the ribbon cable. I emailed BuyDisplay regarding Pins 21 & 22, and they told me to just solder Pin 21 directly to Vcc (Pin 3, 5V on the LCD) and Pin 22 to Ground (Pin 2 on the LCD). Here is a photo of what I'm talking about:

Image

And a video of the final product:


PS I do not recommend ordering the LCD with the header pins attached! Though no fault of BuyDisplay's, the pins were soldered on the "wrong" side of the PCB, and you can't use a ribbon cable that mates with header pins anyway as they are too tall to put the front panel back on.
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By aarb Wed Jun 03, 2020 3:17 am
Do you guys think that the same can be performed on a MPC 60 MKII, since both machines use 240x64 displays? I just wrote a long ass post about it because I'm trying to pull off the same upgrade on my 60, and I'm waiting on parts to get here. The only difference between the old/new is that the 60 uses a 10 pin cable vs the 20 pinouts on the modern Chinese replacements, so I don't know if the signal could be converted with a board or just a plain adapter. Can't source the datasheets for the 60 though, so I'm basically on a plug-n-play trial & error experiment at the moment. :hmmm:
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By richie Wed Jun 03, 2020 3:32 am
aarb wrote:Do you guys think that the same can be performed on a MPC 60 MKII, since both machines use 240x64 displays? I j:hmmm:


If it were that simple, then no one would have to manufacture their own versions to sell for $150-250 each.

There is a possible way to modify the 240x64 LCD's to work on the 60 however it requires a decent amount of modification to it that is out of the scope for most to do.
By Sense-A Sun Jun 07, 2020 8:13 pm
Mad props to vanwerk for finishing what others started. I hope you didn't have to get a new ADDA board.

I still wonder if a resistor shouldn't be in between pin 3 and 21. I guess not since they are both 5volts.

Did you figure out a way to save the contrast settings, or do you need to re-adjust contrast every time you power it back up?

Updated Pinout diagram to make this work:
Image

I am hoping that vanwerk can respond and clarify what he did with pins 10. I assume he connected them.

It also appears that vanwerk soldered pins 1 and 2 (GND ground) together on the new LCD screen.
By Sense-A Tue Jun 16, 2020 8:57 pm
In my diagram, I have a connection between NC pin 20 to NC pin 9. Well, NC means no connection is necessary. So you can save yourself a wire by not connecting those.

I think that PWRGD means...
The Power Good signal (power-good) is a signal provided by a computer power supply to indicate to the motherboard that all of the voltages are within specification and that the system may proceed to boot and operate.


Another explanation says:
PWRGD is an open drain output; asserts low if output voltage is low due to thermal shutdown, overcurrent, over/under-voltage or EN shut down.


I read somewhere about people connecting PWRGD to Vout with a 10K resistor in between... But we already have VEEOUT pin 9 going to VEE pin 20. Another theory of mine is that it tells the LCD to not power up until the voltages are regulated or within parameters in the MPC 1000. This might protect the LCD from an electrical spike when you press the power button to turn it on or off.

Here is an indication that PWRGD should indeed be connected to Reset:
The usual use for PWRGOOD is to hold other devices in RESET, though you could use it (indirectly) to drive a P-MOSFET series switch. The problem is you then have to implement soft start or it can glitch on the inrush current of any downstream decoupling and turn the MOSFET off again! https://www.microchip.com/forums/m614064.aspx


Here is another explanation that suggests that PWRGD and Reset are related:
There are many, many uses for a PG (power good) signal. One of the most common is to control power-sequencing of circuits with many different rails. For instance, you may have a Supply B that is not supposed to turn on until Supply A is on, and stable. By feeding the PG signal from Supply A to Supply B's enable input (either directly, or through some simple logic gates or a CPLD), they will sequence themselves in the proper order.

Another common usage is for reset supervisor ICs. If such a device has an active-low manual-reset input, OR'ing together all the PGs from supplies (assuming each is open-drain), if any of them fail / go out of regulation, the reset supervisor will toggle a reset of the system.

So it's really up to you, but there's two common uses. You should check the datasheet to see when PG is asserted/de-asserted; for some regulators, if they detect you're out of regulation by 7.5% - 10%, the signal will assert. https://electronics.stackexchange.com/q ... l-properly


I would try it first with the two pins not connected. If your new LCD works, then leave them disconnected.
If your LCD does not power up, or flickers, then try connecting them. I do not think it will blow anything up. As a further precaution, plug your MPC 1000 into a power conditioner. You know, like a Furman Power Conditioner or a "rack rider." Perhaps a high quality surge protector would be sufficient. This may help prevent any spikes in electrical current during power up and power down while you are testing.

The most important thing is not running a power cable to ground. And using a plug with ground, and making sure your power outlet has ground. And don't confuse which pin is pin 1. Match up pins carefully.
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By horisonten Sun Jun 21, 2020 3:07 pm
Apparently you don't need to bridge pin 1 and 2. I can not seem to find Vanwerks original picture with his comment on Imgur atm. But he wrote this as a caption:

"Note: it is not necessary to form a solder bridge between pin 1 and 2. I took the picture while I was experimenting. I no longer have the pins connected and it works fine".
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By horisonten Tue Jun 23, 2020 5:47 am
I just saw your PWRGDB comment Sense-A. I tried to find information about it as well yesterday.
It feels like they (pins 10) should be connected, but it feels a little unessecary to take a chance.

I find it very strange that people who have managed to install it won't share the exact details :Sigh:
I can not seem to understand why. Are they so eager to start selling their own solutions?
Well I will get my BuyDisplay LCD in a couple of weeks. I'll post the correct details if I get it working, so that we can put all uncertainties to rest.