LUCAS & FRANCES Boards, PAL Code & PCB Masks

[Kai]

Yet another gift of awesomeness for you people, the LUCAS Accelerator, and the FRANCES memory expansion board, as detailed in Amiga Transactor Magazine from December 1988 and August 1989 respectively

Originally designed for the Amiga 1000, but i see no reason why this shouldn't work in the A500 or A2000

LUCAS

http://kai.supramania.com/Electronic...MIGA/LUCAS.pdf

The article contains all the PAL code you should need to make this work.

FRANCES

http://kai.supramania.com/Electronic...GA/FRANCES.pdf

http://kai.supramania.com/Electronic...GA/Frances.lha

The LHA contains the PAL code in .jed format, ready to burn onto your PAL/GAL, and the article lists the code itself. Unfortunately, there's no ready PCB mask i can find, but, it's a start!

*EDIT 26-10-2017 : LINKS UPDATED! *

[Kai]

26 views and no comments?

[prowler]

You'll have to wait for EAB's hardware enthusiasts (like Kipper2k, Loedown, Zetr0, etc.) to come online.

Sorry, I already have a CS-PPC in my A4000.

[rkauer]

All my A500 have some sort of CPU enhancing, but I don't mind if a kind soul do a produce run on this.

Then I'll buy at least one unit.

[Kai]

I said this was for A500/1000/2000

[roy bates]

i like this alot

[Loedown]

Originally Posted by prowler

You'll have to wait for EAB's hardware enthusiasts (like Kipper2k, Loedown, Zetr0, etc.) to come online.

I am always online , my A2000 has a GVP '030, my A4000 A3640 and my old A500 is an inherited one from a dead friend which will remain unmodified.

I just sold my A1000

Kai is doing a great job of providing some obscure circuits and information on some obscure hardware, it's people like him / her that make my life so much easier, especially when I am fixing old and obscure hardware, just like the Moog Rogue on my workbench which is finished apart from a mild retuning of Oscillator B in the high end, it's been on for the last hour warming up

[whiteb]

What is the go with Lucas/Francis ?

I have read posts on the internet from people saying that the boards were *Extremely* noisy electrically, and it was touch and go to get it working near properly.

[Loedown]

Originally Posted by whiteb

What is the go with Lucas/Francis ?

I have read posts on the internet from people saying that the boards were *Extremely* noisy electrically, and it was touch and go to get it working near properly.

Susceptible to noise or transmitted noise?

Sounds like a board design issue.

[Zetr0]

@Kai

WOW, totally missed this thread, my thanks for sharing... these are MUCH better than the skimpings I found on Aminet a few years back.


With the review I have done with the LUCAS / Frances it would be better to develop an all in one board (something with 4/8MB), and reduce as much as the hard logic as possible into fewer CPLD's

The noise is a compound issue, reading the sources there is a pickup (probably board design) and a subtle syndrome of effect due to the logic on the card - Having the PCB's manufactured instead of running a national ferric-chloride day would reduce the noise issue, But with not much ado, one could easily see 16-25Mhz confortably.. with a bit of rework and reducing chip counts to a larger CPLD I recon 33MHz would be attainable.


Thanks for sharing Kai!

[Kai]

No problem - i find this stuff for fun....now if anyone wants to sell me an A500+ for cheap

The only issue i can forsee with the FRANCES board, is the DRAM controller was EOL'ed a long, long, long time ago - and only Chinese IC Reclaimers seem to sell them. The PAL's used are still easily available, and the code is all there, which wouldn't take too much effort to turn into an FPGA design, although, that makes it 'less accessible' for the home hobbyist, as SMT soldering is not something fun, or easy to do without the proper equipment.

I tried using Eagle to turn the LUCAS into a proper PCB layout (all the components are listed in Eagle Libraries), but i cant find an easier way of linking the bus's from the FPU to the CPU and the 68000 socket - without it, its a mess to keep track of (96+ lines, all confusing!).

I don't mind creating an integrated board in Eagle for everyone, if someone can recommend a replacement DRAM controller, and tell me how to easily link address and data bus's in Eagle!

[Kai]

Hold the presses! Don't pay any attention to the PCB Masks i uploaded - they're NOT for the LUCAS (i didn't read carefully enough!) - they're for a Macintosh, its a 68020 design from XLR8.

However, back to my previous post - i redid the schematic for LUCAS in Eagle, but OWIE my brain hurts (i figured out how to do Bus's properly):



So, the schematic is all done, but routing a PCB Layout? NOT FUN! O.o

I might have to go with a 4-layer board to make it easier...

[Kai]

...routing...done....brain...aching!

Well, here we go folks - just a preliminary, but, this is a 4-layer PCB (very hard to do as a 2 layer), the component arrangement could probably do with working out, and trust me - you're welcome to have a go - i'll upload the .sch and .brd if you like

Anyway, behold:

[rkauer]

Woho!

Which is the actual size of the board?

Also, any chance to add large internal ground planes to keep the noise generation low?

[pandy71]

@Kai - please send/upload/attach eagle sch - maybe next weekend (if i found some time slot) i will try to make PCB (at least partially) - remember about component placing - this is crucial.

[Kai]

The 4-layer board includes a ground layer, and a +VCC Layer. Power comes in from the 68000 socket, straight to that layer, and feeds every other IC on the board.

Pandy - sure thing, i have a feeling i neglected the VCC and GND for the Glue Logic - you might want to double check it - it looks like a mess...because it is

http://kai.supramania.com/Electronic...PU%20board.sch

[pandy71]

Kai THX! and no problem - can't promise anything but i will try to check component placing and maybe some traces routing.

OK, seems that my Eagle is not able to create board bigger than 80x100mm - to small even to place components... KiCAD is not able to import libraries and schematics from Eagle - today i give up...

[Stedy]

Kai,

You are aware that the original files have been available since 1993 @ FTP://ftp.funet.fi/pub/amiga/hardware/accelerators ?

You have missed the decoupling capacitors from your schematic, they are essential for it to work. To improve the design, some SMT parts would help, notably on the resistors, capacitors and clock crystal. This will simplify layout and in the case of the clock crystal reduce the EMI emissions.

GALS and PALs are obsolete, the 16R4s and 16L8s went out of manufacture years ago.

I can't release it right now as I need to tidy up first, but I have the core logic from this + a few other bits targeted at a Xilinx XC9572 CPLD from my abandoned accelerator project. You can buy PLCC parts if you are desperate to avoid SMT parts.

Ian

[Kai]

If i was aware, i'd never have started the topic

Yes, i'm aware i missed out the decoupling caps, the only thing is the schematic makes no sense as to WHERE to put them.

PAL 16L8: http://uk.farnell.com/texas-instrume...-ic/dp/1605238

PAL 16R4: http://uk.farnell.com/texas-instrume...gic/dp/1652253

Out of manufacture, you say...?

SMT Parts would be a lot simpler - but less accessible for the home hobbyist to assemble. Easy to substitute the parts in Eagle, just change the package, without changing the values or placement.