Icky - Progress

[exxos]

Looks that way. Now I need to find me a new DMA chip now

I will try and look through my scrapper boards this week... I need to collect chips,connectors etc for my board which seems to be getting nowhere fast , so if theres a spare you I will send it you.

[exxos]

Icky, was it you who soldered the cap across the floppy power because of problems ? Thinking after the current chaos, it might be worth trying without it now...

[Icky]

Icky, was it you who soldered the cap across the floppy power because of problems ? Thinking after the current chaos, it might be worth trying without it now...

Yes it was me and I have taken it off during all this chaos. Things are working well without it.

[exxos]

Yes it was me and I have taken it off during all this chaos. Things are working well without it.

That's good news. Really the board should be able to run without any of the larger caps.

[Icky]

So going back to my list of things to do again after all the NASTY DMA / WD1772 chaos:

• COMPLETED - Scart Cable - flicker and bounce gone with cable update. Cable clean-up also sorted out the sound a while back
• COMPLETED - Un-f*ck board installed
• COMPLETED - Seeing slight noise scrolling up the screen. Modifying cable to improve grounding and shielding did not fix. Seems to be dependant on the noise of a PSU. Gone away after using one that is not so noisy.
• COMPLETED - Keyboard / Mouse - getting key repeats and sometimes when moving mouse. ACIA area (DILs) were poor in quality so I replaced and checked the dataline patch. In addition made a smaller pin8 patch socket instead of the extension cable I created. Adding longer lines to the keyboard requires more juice to the board but repeating has gone
• PATCHED - External Floppy Drive. Tested after patch wires in place. External floppy works. Now needs a STF REMAKE FLOPPY UN-F*CK BOARD. What this has allowed me to do is test out SpectreGCR which shows External Floppy and ROM Port is all working as expected
• COMPLETED - RS232 - is working. Helped with DiagRom and Diag Cart but noticed it got corrupted when board has more power applied i.e. with keyboard, mouse, floppy etc board takes more amps. This has gone away with the ACIA clean up so something must of got cleaned up on the way. Turns out a patch is required - spotted by PaulJ
• COMPLETED - ACSI - Oh wow this was an adventure. Plugged in a while back and it occasionally saw the Megafile but no drive. Now its not even seeing the Megafile. When booting with Megafile attached now at start it doesn't recognise the floppy drives. Exxos has created a WD1772 buffer board and thread on this https://www.exxosforum.co.uk/forum/viewt ... =19&t=1260
• NOT STARTED - Parallel - No tests yet have realised I have no old cable or a printer to connect it to. May be one of the others can test if they have a suitable printer etc - suggestions on how to test - not explored yet.
• COMPLETED - MIDI - Tested and working for IN & OUT

Also I have a few of my own lessons learned through this whole experience:

• I'm rubbish at soldering as there have been a few bad joints but I did not burn myself
• Don't use lead-free solder - I cant blame my bad soldering on lead free solder but after sanford's post https://www.exxosforum.co.uk/forum/viewt ... =35&t=1263 it has made me think not all my soldering faux pas are due to me. There are a lot of joints that have that fuzziness on the joints
• For an ALPHA board use turned DILs - From my experience with the normal DILs and having to put in chips that have been taken from a donor board. Even the slightest bit of solder left on the legs can cause you to pull out the DIL socket connectors. Have had to replace WD1772 and ACIA sockets with all the pulling in and out whilst problem solving
• Always expect the unexpected - this is a given weird sh*t happens - NASTY DMA / WD1772 as an example
• Be prepared to break stuff - Bending pins out and back and out again. it doesn't matter how careful you are a pin will come off
• Always check Exxos' connector wirings and pull-ups - couldn't resist that one

Question is what do we test next?

[exxos]

Blitter

[PhilC]

I'd get the tester out first before removing those jumpers though, as it killed one of my Glues.

But good luck.

[Icky]

Blitter

Ordered socket but don't have a Blitter - they are hiding somewhere cant find one for sale anywhere

[Icky]

I'd get the tester out first before removing those jumpers though, as it killed one of my Glues.

But good luck.

When or if I get my hands on one of those hidden gems - I will keep that in mind.

[exxos]

I sold out of blitters its one reason I'm trying to do the the fpga version.