BT-USB-Hybrid controllers for Model M 122, M2, Unicomp M

Please make a BT-USB-Hybrid controller for other Model M variants:

Model M 122
13
42%
Unicomp Model M/Model M 4th generation/Lexmark Model M
11
35%
Model M2
7
23%
 
Total votes: 31

User avatar
ScottPaladin

07 Jun 2018, 16:20

I'd love to convert one of my Lexmark Ms.

mind_prepared

07 Jun 2018, 23:57

ScottPaladin wrote: I'd love to convert one of my Lexmark Ms.
Do you have an idea how to deal with the lack of an SDL bay? The only preexisting opening is the hole where the PS/2 cable exits the case. This opening could be used to hold a Mini or Micro USB connector, but it would have to be glued or screwed to the inside of the bottom shell.

Since all Model M bottom covers, including 4th generation boards, seem to have retained mounting pins for the 170x50 mm controller boards, I would want to use them to hold the controller board and make a daughterboard to replace the original controller boards mounted in the top right corner directly below the LED overlay. The daughterboard then would have to be connected to the main controller board by ribbon cables.

However, my current design requires the user to throw a switch to change between BT and USB mode - but there are no preexisting openings, or at least no other suitably sized openings, for a slider or rocker switch in the cover of a 4th generation Model M. I could modify the circuitry so that the mode of operation will change automagically once a USB cable is plugged in though, but that would exclude special use cases (s.a. charging the battery while in BT mode).

What do you think?

User avatar
ScottPaladin

11 Jun 2018, 16:39

mind_prepared wrote:
ScottPaladin wrote: I'd love to convert one of my Lexmark Ms.
Do you have an idea how to deal with the lack of an SDL bay? The only preexisting opening is the hole where the PS/2 cable exits the case. This opening could be used to hold a Mini or Micro USB connector, but it would have to be glued or screwed to the inside of the bottom shell.

Since all Model M bottom covers, including 4th generation boards, seem to have retained mounting pins for the 170x50 mm controller boards, I would want to use them to hold the controller board and make a daughterboard to replace the original controller boards mounted in the top right corner directly below the LED overlay. The daughterboard then would have to be connected to the main controller board by ribbon cables.

However, my current design requires the user to throw a switch to change between BT and USB mode - but there are no preexisting openings, or at least no other suitably sized openings, for a slider or rocker switch in the cover of a 4th generation Model M. I could modify the circuitry so that the mode of operation will change automagically once a USB cable is plugged in though, but that would exclude special use cases (s.a. charging the battery while in BT mode).

What do you think?
Well, both of my Lexmark M's have SDL bays, so I hadn't really been thinking about how to work around the lack of one. I'm not one to balk at cutting a new hole though. Couple of files and maybe a 3D printed shroud solve most problems of that type.

I'm partial to having a physical switch to choose mode, even if it means I've got to cut the plastic to make room for it, but I know not everyone would agree. A possibility would a three position switch: force USB, force BT, and cable select. That would give a lot of flexibility, and anybody who wants to use cable select could just solder/jumper into cable select mode.

mind_prepared

11 Jun 2018, 19:49

ScottPaladin wrote:
Well, both of my Lexmark M's have SDL bays
in that case there is no problem at all. My reservations only apply to 4th generation boards, the last revision of the M series without an SDL bay and a fixed cable exiting the case at the top right corner. If your board has an SDL bay then you're good (whether your controller has an SDL connector + SDL cable doesn't matter) :)

mind_prepared

23 Jul 2018, 01:31

ok, I'm making another batch... unfortunately the last run sold out so fast I didn't get around to making any M122 conversion kits. The prototype I made is sold as well. This time around I'll make 16 controller boards and 9 daughterboards to connect the M122 matrix. An M122 conversion kit will consist at least of the controller board and the daughterboard btw.
I'll also prepare a daughterboard for 4th generation boards in the very near future, so all you Lexmark/4th generation guys stay tuned, soon you'll too be able to convert your board to USB+BT. =)

Let me know if you're interested and I'll count you in.

ConiKost

12 Sep 2018, 23:33

So, any news on this?

mind_prepared

13 Sep 2018, 12:52

ConiKost wrote: So, any news on this?
YES! Absolutely! The controller boards are done, the daughterboards are done and I'm ready for taking actual orders and shipping now. I'll post a picture of a complete kit in a bit.

The only reason I didn't get back to any of you guys earlier is that I had problems with a new milling motor I bought to cut the FR base material to size and RMA'ing took a while, and then I went on holiday for a week.

So if you're still interested PM me.

mp

mind_prepared

20 Sep 2018, 01:03

I've edited the original post to include a picture of a complete M122 conversion kit (although a few things are not in the picture)

mind_prepared

14 Oct 2018, 17:34

hey guys, just letting you know I've finished designing and prototyping a daughterboard to add support for 4th generation Lexmark/Unicomp boards.

With the addition of a few transistors the controller can be configured to automatically switch from USB to BT mode and vice versa whenever a USB cable is attached/detached, not a big deal. The small opening where the original PS/2 cable enters/exits the cover can be used to break out the USB port, preferably using a panel mount Micro USB connector or something like that that will fit in there.

How about it? Anyone wanna give it a shot?

mind_prepared

23 Dec 2018, 16:40

Except arakula I haven't heard back from any of the guys who voted for a M122 replacement controller. What's wrong fellas?

Also, I see there's 7 votes for an M2 replacement controller - but only guy has left a message so that I can add him to the list of people interested.
Please, if you're interested in a replacement controller for your M2, do leave a message so that I can add you to the list, anonymous votes aren't really worth anything, I need to be able to get in touch with you guys in order to check back when the time is right!

Appreciate it

Cheers

mp

Excelso

23 Dec 2018, 19:58

I would be interested in a Model M 122 kit but I'm unaware of how much would that cost.

mind_prepared

24 Dec 2018, 02:26

Excelso wrote: I would be interested in a Model M 122 kit but I'm unaware of how much would that cost.
the controller board is 75€ with BT+USB and 67€ without BT components, the daughterboard is 10€ and the jumper cables are 5€.

Post Reply

Return to “Vendors”