New microdrive internal replacement

[Popopo]

Some updates.

I am building up the mDrive replacement, well... I have found some issues that I Couldn't see before. Not very problematic actually but I would like to work on them.

Firstly... the first board placed on MDV1... MUST be underboard fitted. Why? because in other case, the chassis will choke with the RasbPi USB connector... That's why, on the photos published by Dr. Gusman (the author) first mDrive is under the PCB (hidden). That's why.

Some pictures:


It is solved as I described it before (but I didn't know why he did it, now I know it).
Some pictures to give the idea:


it may be with female and male connector just... be aware with Hermes IC, it fits but... not to much so some adjustment of pin length could improve it. Just in case you add female connector under PCB. Next photos shows results:




Last point:
After opening it and removing the mDrive... I can tell that voltage regulator on PCB emulator doesn't need to stay on that way, could be settled vertically on the bottom side. Without bothering cables at all. There is nothing. I would like to work in a version that set the regulator in another place.


Also move the connector IDC to the left to get it over the PCB connector. Even to replace the U1 (voltage regulator) where the head of J2 is now.

Some... maybe tricks that I see while writing this post... it seems to me that we don't need IDC connector at all. Morveoer when we don't want to replace original connector on QL board. Some pins male 2x7 with those cables from Arduino to directly the PCB connector should do the work nicely. Ouh yeah!

Well.. that's all folks. Some experience and ideas share


Edit:
I forgot the screw from mDrive (left-corner side) doesn't match with the PCB, get too high, it needs something to get properly fixed.

[Derek_Stewart]

Hi,

Why not use low profile pin to arrangement to reduce the clearance of the PicoPi micro usb connector over the IPC.

Or use a straight pin that will be soldered to the PCB and PicoPi, with plastic spacer to give the correct clearance.

I have ordered some Drive and Cartridge PCBs to make one and show watch I mean.

I just wonder looking at the KiCaad PCB file, if the PicoPi for MDV1 could be altered to have the PicoPi on top, this means having rerouting the Drive PCB for MDV1 and having a separate PCB for MDV2.

Or rotate the PicoPi through 180 Degrees so that they are facing the opposite direction, a bit more PCB work there.

[Popopo]

Hi,

Why not use low profile pin to arrangement to reduce the clearance of the PicoPi micro usb connector over the IPC.

Or use a straight pin that will be soldered to the PCB and PicoPi, with plastic spacer to give the correct clearance.

I have ordered some Drive and Cartridge PCBs to make one and show watch I mean.

I just wonder looking at the KiCaad PCB file, if the PicoPi for MDV1 could be altered to have the PicoPi on top, this means having rerouting the Drive PCB for MDV1 and having a separate PCB for MDV2.

Or rotate the PicoPi through 180 Degrees so that they are facing the opposite direction, a bit more PCB work there.

Soon you will understand me or I will understand you.
For mdv1 I soldered directly onboard. No pins at all. so not possible to get lower profile.
If you wanna put it on the bottom, that is better, I put two ideas, straight pins (that is OK) and even with socket, that is OK too, a little tight but OK.

About modifications, also I want to try something to try to improve the PCB localization. Now rethinking about connectors... not everything needs to be on the top face, also many things could be on the bottom, like the voltage regulator or before IDC connector.

It is a nice board and can be improve it. Why not?

[Popopo]

Hi,
I got to this dead point... trying to solving how to wire it... I got that...




So no idea how to wire it, in service manual I didn't get a proper pinout with signals assigned.
Probably lack of skills to understand it right.

[Pr0f]

What's the query with the connector?

Is it the 9v feed from the QL board to the Microdrive unit - this is correct - it's used to power the motor / and on board regulator chip.

[M68008]

Forget what you labeled the "mDrive bus": That's the PCB connector on the side of the QL, for external microdrive units, and it has a different pinout.

In your case, my understanding is that you'd like to connect the MDV replacement's connector to the connector on the QL motherboard. From the initial schematic in this message thread, it looks like the two connectors have the exact same pinout.
I would double check the 9V voltage on the MB to make sure of the correct orientation.

[Popopo]

Breaking NEWS!
Soon V2 is coming soon.
Already a V1.1 is published.

Future changes on V2

• Pico will be on the back side

=> solving some fit issues with case for MDV1.

• Voltage regulator changing positions

=> to allows to solder on the back side too, saving space and doing it more clear to place, solder and close the QL Case for MDV2.

• Homogenization of Tracks length

=> firmware won't bother about propagation signals differences, doing it more reliable and easier to improve firmware if needed. Hardware will not be a factor anymore.

[Popopo]

What's the query with the connector?

Is it the 9v feed from the QL board to the Microdrive unit - this is correct - it's used to power the motor / and on board regulator chip.

The query (no I got the answer from the Author) is that on the board and scheme from Maintenance Manual, there is not any reference (that I could see) to identify properly and visually the signals from Board (QL) connector with signals that each pin has. Thus when I Tried to match the pins signals in the mDrive board with the pin signals on the QL board... I was unsuccessful and frustrated.

Pin 1 logic (signal ID) on QL board doesn't match Pin 1 on MDV emulator.

[Popopo]

Forget what you labeled the "mDrive bus": That's the PCB connector on the side of the QL, for external microdrive units, and it has a different pinout.

In your case, my understanding is that you'd like to connect the MDV replacement's connector to the connector on the QL motherboard. From the initial schematic in this message thread, it looks like the two connectors have the exact same pinout.
I would double check the 9V voltage on the MB to make sure of the correct orientation.

Exactly,
Thank you, both connectors have the same pinned order localization. 9v has the same pin position.
At any case... I wonder... (because I failed about it) how to find out that from the service manual?. (to don't bother with more similar questions if I can find the answer on the available docs).

[M68008]

At any case... I wonder... (because I failed about it) how to find out that from the service manual?

The service manual shows the connections here:

I guess Sinclair left it as implicit that the other end of the cable has the same pinout.