exxos's Atari, Amiga & retro forum

It looks like the main bottleneck is linking the DRD lines from the shifter to RAM.. No so easy to route on the VCC layer as the GLUE is already routed there

The only way it could be done is if I routed it on the GND layer Though splitting the GND between the CPU & Shifter could actually be a advantage, as it may help keep some noise from the CPU away from the shifter GND...


Also going to have to be careful of the PSU holes.. as if the metal feet of the PSU bracket may overhang the holes and short the via's out

You could insist that the front feet are insulated with something like a fibre washer but still use the rear slotted mounting for earthing etc?

PhilC wrote: ↑Sun Jul 28, 2019 11:25 am You could insist that the front feet are insulated with something like a fibre washer but still use the rear slotted mounting for earthing etc?

Its better for the PSU plate to be connected to GND.. But as people never read instructions, someone would put the PSU on the board and blow the thing up Its fixable, just will take a bit more time.

I'm thinking if I shove the SMT GLUE over to the left more, it will free up room to the right of the SMT GLUE and have space on the VCC layer to route the shifter datalines back to the RAM.. If I route those lines close to the PSU holes (which will have to be anyway) the autorouter won't be able to place via's there because there will be tracks in the way.. It should also free up the mash of tracks and route a whole lot better afterwards.. so win win win

Started routing the shifter data lines.. I was using the auto route tool to try and speed things up, but it just ended up putting millions of vias everywhere So I started manually moving stuff around and that is why it looks terrible on the routing so far. Though I have managed to remove all the vias, so I just need to tidy it up now

Sometime later...



Next up to see where the next bottleneck is on the PCB..

Last time it routed in 1698 via's.. so be interesting to see what it routes with this time...

Nicely done !

Ironically it seems 46% of the PCB has already been rooted manually so far

Is looking pretty good so far...


BUT..




I am hoping this sort itself out later...

Basically the top layer is being jumped over with via's over a tray switches on the vcc layer..

So its like starting on the top layer,Jumping over tracks which are on a different layer, and then jumping back to the top layer I seriously think this autorouter is on LSD or something..

Finally got Trudie fitted in with the mods done..

Now to figure out some firmware...

So far not going well... seems to be a crash screen generator.. so some bad joints somewhere to track down..


bypassed the PLD so its basically a CPU adapter PCB at the moment...