So…I just scored a broken Boss DR.202 that I’ve spent the day repairing. I got it to work, but the LCD display and its associated ribbon cable connector is missing. Any ideas on a replacement? Here’s the service manual for reference.
The part is “CM1621-OS”. Not sure if that helps…
from the schematic it seems to be a standard LCD (HD44780 like) but not connected in normal way on the connectors. (the pin 1 on the DR202 schematic is the contrast for the LCD, we can recognize a PWM/dc converter circuit)
it seems to be a 16 character 2 lines standard LCD but with non standard wiring.
the LCD connector is a flat cable ^ ^ (white in the middle right)
it will not be easy to replace it if you can’t find the original part unfortunately.
the last solution is to find a LCD who mechanically fit inside the original part dimensions and solder the wires in place of the FPC connector with the right pinout but it will requires some electronics skills.
edit: it will really not be easy!
as you can see here:
and on the picture, the LCD is COG (chip on glass) model so there’s really not free space to use a standard model with bezel. but perhaps you can find one from digikey or something like that. and perhaps choose an oled version with compatible controller instead of LCD.
here is the right wiring for a “standard” 5V LCD with “HD44780 like” controller (KS0066U)
Holy smokes, Genesis! This is great info! I’m down with hard wiring the molex connector on the PCB directly to a new LCD. Thank you so much for your help…searching for a HD44780 as we speak…
HD44780 is the old chip. now it’ KS0066U
check the pinout of your LCD with the signal names to be sure before to do the wiring.
I found some HD44780 on mouser. Gonna take the plunge! Dude…thanks again, especially for the correct wiring info…that makes all the difference…
no problem. I’m pretty sure it will work.
double check the size 16 characters 2 lines it’s important for initialization commands.
Excited. 16 x 2 indeed. This groovebox has got to be one of the coolest machines ever, but it’s tricky to navigate without the LCD…
This is what I’m about to order…
be careful such LCD is very thick and the backlight consume lot of power .
wait a moment I will check mouser
This might be an option as well. They all seem to be pretty thick in comparison to the original LCD. It’s doesn’t have to be pretty…as long as it works!
check this one, the backlight is white:
backlight current is 20mA instead of 70-100mA for your ref
and the white is better than the old yellowish green (570nm)
Hey! That looks way better…and it’s thin.
no this one is not thin 13.5mm.
when you choose a led backlighted one the thickness is at least 8.5mm
I hope you will be able to modify the boss case
I see! There’s lots of space on the case and lots of depth, too. I like the one you recommend, since it is backlight, but doesn’t seem to require extra power for this feature.
Well…what a great way to spend a sunday…this drum machine has gone from zero to hero over the last week. Thank you for all your help Genesis! I owe ya…
remember, double check wiring (triple check VDD and VSS order because it’s destructive) before to turn on the unit and post if all is ok
don’t forget to connect the pin 15 to pin 2 and the pin 16 to pin 1 to turn on the backlight. the current limiting resistor is on the LCD as they claim.
Yup! I bought 4 of those LCD’s just in case. I will absolutely post when it’s all fixed up. Merci, monsieur, et merci pour votre aide précieuse…