Sporniket's log on hardware stuff

[ijor]

I am not sure of the directionality of some signals, though..

I can probably fill this gap. Which ones?

[sporniket]

Thanks @ijor .

First, I made the pins for /AS, /UDS, /LDS, /DTACK and R/W bidirectionnal, but now that I write that, I realize there is no pins to request bus mastering (BR/BG/BGACK) so I guess they are in fact input only ?
Then, I supposed that the pins for /RAM,/DMA,/DEV,/VSYNC and /DE all comes from the GLUE, so I made them inputs, am I right ?

[ijor]

First, I made the pins for /AS, /UDS, /LDS, /DTACK and R/W bidirectionnal, but now that I write that, I realize there is no pins to request bus mastering (BR/BG/BGACK) so I guess they are in fact input only ?

They are not bidirectional. But DTACK is output, not input.

Then, I supposed that the pins for /RAM,/DMA,/DEV,/VSYNC and /DE all comes from the GLUE, so I made them inputs, am I right ?

That's correct. Technically, VSYNC can come from GLUE or externally from the monitor port. Remember that the ST supports external sync.

[frank.lukas]

DISCLAIMER : my installation will be unconventionnal, as I have to get enough clearance to install an IDE extension provided by @frank.lukas. And with the original big cap, I have a problem when trying to install the extension with a Compact Flash adaptor and said Compact Flash card :

What are your problems with my STE IDE Interface ?

Use HDDriver to partition your CF card. 500MB for each partition.

[sporniket]

@frank.lukas for now I guess I don't have a problem with the hardware. About the fitting, the clearance problem is solved once the big capacitor has been replaced by an alternative positioned more toward the left, to leave space for the whole thing (the interface + the compact flash adapter + the compact flash)

I also have to put the jumper for the powering, I did not understand whether it is J1 or J2 ?

For now I am stuck with creating an image disk to copy into the compact flash. (I also admit that I did not try a lot of attempt) I don't have Hdd driver and my only attempt with formatting an image using AHDI did not work.

[frank.lukas]

I also have to put the jumper for the powering, I did not understand whether it is J1 or J2 ?

one pin goes to ide port pin20 and the other is vcc so you have to bridges the two with a jumper to power the cf adapter

You can use ahdi 6 to set the cf card up. Use hdx to partition the card ...

[sporniket]

Thank you @frank.lukas. Unless unforeseen events, I will have some alone time very soon, I will do my best to complete the setting.

@ijor, I did fix the directionnality, thank you.

subsheet_100-U15–MMU ; U22-23-26-27–Bus isolator.png

edit : typo

[sporniket]

This time, I try to advance the PCB and the schematic at the same time...

Capture d’écran du 2022-07-10 10-06-03.png

Capture d’écran du 2022-07-10 10-06-43.png

[sporniket]

Ready for the next part of the schematic...

Capture d’écran du 2022-07-12 21-29-51.png

Having the scanned pcb is helpful to have some approximative guidelines (I must average between the top scan and the bottom scan, and I still need the original scan to distinguish better how the traces are going : the vectorisation loses a lot of details.

[sporniket]

Next subsheet, the RAM chips. I succeeded to pack them all.

subsheet_101-U16-17-19-24-25-28-29-30-32-33-34-38-42-43-44-45-RAM.png