how to verify if a multiface 1 is working correct ??

[1024MAK]

Two things:

The Opus has its own bank switched / paged ROM/RAM system, so there must be a switch or something to prevent clashes between them.

The MF1 looks to be missing a lot of logic chips.

Mark

[jojo]

i took all those chips off to verify them in a component tester

i will try to get some sense into the opus coming weekend ,

Need the formatting programm to do so on a pc-floppy .

Anyone ?

[jojo]

the only result at pressing the nmi-button is speccy reset.

i verified the eprom , and it is ok ( verified against download )


Any ideas ?



- i have ordered the multiface remake pcb , so in an attempt to see if that one works on theis "frankenstein"build spectrum.

[1024MAK]

Ahh, I was going to reply the other day, must have forgotten

As the Opus also uses it's own ROM, has the previous owner fitted or modified the MF1 board with a switch or some other method to disable/prevent it's ROM and RAM from being paged in?

Mark

[jojo]

Hi mark ,

nothing specific on the front of the pcb ,

Or on the back ,

only multiface enable and the nmi switch have been extended to some wire-posts

all ic's get their 5 volt .

- i have ordered the parts to make a new multiface to try on the output connector of the opus , see if that will work ( need time to get that unit build ) .

[jojo]

now waiting for the last components to arrive , and then do some basic testing on a speccy , and if that works well i will put it on the extender connector of the discovery to see if it works there too .

- might be needed to remove the diode on the multiface one

[Paul]

Have soldered the edge connector?
It seems to be on the wrong side of the PCB and the plastic end parts need to be taken off.

[jojo]

Was only a mock-up , connector not soldered !!

[jojo]

okay ,

finally came to testing the new pcb , and ......

It is only partly working ;

i get the multiface-menu after pushing the nmi button .

BUT , it looks like i can not select any options ( aka there is no keyboard response )

What might be causing that ?? - tried on a stand alone speccy 48 -



= i noticed that WHEN i can give the multiface a command it only is possible when it looks the screen is being refreshed( looks like a slight blinking taskbar .....)