Search found 307 matches

by bprosman
Thu Sep 12, 2019 7:24 am
Forum: acorn atom and system
Topic: Atom mini-tape drive...
Replies: 6
Views: 146

Re: Atom mini-tape drive...

When I was young (many moons ago) I someone made one based on a P2000 (Philips) micro drive.
If I recall correctly it was Chris Kwakernaak (RIP).
by bprosman
Tue Sep 10, 2019 6:43 am
Forum: hardware
Topic: Cheap Xilinx LX9 Starter Board
Replies: 30
Views: 4015

Re: Cheap Xilinx LX9 Starter Board

Thanks for your reply and explanation Jason.

Kind regards , Bram
by bprosman
Mon Sep 09, 2019 11:29 am
Forum: hardware
Topic: Cheap Xilinx LX9 Starter Board
Replies: 30
Views: 4015

Re: Cheap Xilinx LX9 Starter Board

The purpose of the schotty diode on the new adapter design is to prevent back-flow of current, in the event the FPGA board is powered from the USB port, and the host system is switched off.
Indeed, now I recall , was lost in "space" (aka my brain).
by bprosman
Mon Sep 09, 2019 10:55 am
Forum: hardware
Topic: Cheap Xilinx LX9 Starter Board
Replies: 30
Views: 4015

Re: Cheap Xilinx LX9 Starter Board

One more question.

Instead of using a Schottky diode to transform the 5V from the "Host" system into 3V3 would a voltage regulator add any benefit ?
by bprosman
Mon Sep 09, 2019 10:45 am
Forum: hardware
Topic: Cheap Xilinx LX9 Starter Board
Replies: 30
Views: 4015

Re: Cheap Xilinx LX9 Starter Board

Hi Dave, is that GODIL's level shifters (with 1.5K pullups) do cause real problems on many systems In that case the BSS138 solution would have the same issue ? That's why I think on the long term it would be better to have dedicated 74F "push-pull" based adapters for each of the supported processors...
by bprosman
Mon Sep 09, 2019 10:24 am
Forum: hardware
Topic: Cheap Xilinx LX9 Starter Board
Replies: 30
Views: 4015

Re: Cheap Xilinx LX9 Starter Board

Looking at Jason's level shifter board, it looks it is a copy of the level shifter part of the Godil, including the resistors and the same IC's. @David - Hoglet But weren't the resistors the parts that caused issues ? (like in the MPF-1?) What I understood from our previous discussions is that you c...
by bprosman
Sun Sep 08, 2019 7:10 pm
Forum: hardware
Topic: Cheap Xilinx LX9 Starter Board
Replies: 30
Views: 4015

Re: Cheap Xilinx LX9 Starter Board

I'm trying to figure out how Jason's level shifter board is working. I do understand the working of this one : http://www.ti.com/lit/ds/symlink/sn74cb3t16211.pdf Bit puzzled though about the resistors used. Are they in series with the 5V DIL signals ? //Edit, looks like its the same sort (connection...
by bprosman
Mon Sep 02, 2019 7:47 pm
Forum: other vintage computer hardware, software and games
Topic: What brand/type of FPGA
Replies: 11
Views: 660

Re: What brand/type of FPGA

Last week I picked up 3 Spartan 3 development boards. I do realize they are outdated but 2 of them have an xc3s200 and one is an xc3s1000, the latter still is big enough I think for large experiments. And I got them very cheap. It's this board : https://www.xilinx.com/support/documentation/boards_an...
by bprosman
Mon Sep 02, 2019 5:44 pm
Forum: for sale / freebies
Topic: R6532-11 RAM I/0 Timer
Replies: 5
Views: 180

Re: R6532-11 RAM I/0 Timer

Hi Dave,

Would you also ship to NL ?
What would be the shipping costs ?

Kind regards, Bram
by bprosman
Fri Aug 30, 2019 8:10 am
Forum: acorn atom and system
Topic: AtomSID v1.8 PCB files.
Replies: 10
Views: 422

Re: AtomSID v1.8 PCB files.

Nice, would it also work with the SwinSID ?
https://ilesj.wordpress.com/2010/11/21/ ... placement/
by bprosman
Tue Aug 20, 2019 2:04 pm
Forum: acorn atom and system
Topic: ICE T65/Z80/6809
Replies: 658
Views: 56973

Re: ICE T65/Z80/6809

Yesterday I finished my "ICE-T Command Reference Manual".
Initially written for my own use , but publishing it here for everyone that thinks its handy.
ICE-T_Command_Reference_Manual_V1_1a.pdf
(2.17 MiB) Downloaded 19 times
by bprosman
Sat Aug 10, 2019 10:12 am
Forum: hardware
Topic: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).
Replies: 16
Views: 311

Re: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).

Nothing really odd. A little case with some Arduino stuff but my son (22) took his laptop for the first time so we’re with 2 now. Mainly playing with Kicad.
by bprosman
Sat Aug 10, 2019 9:56 am
Forum: hardware
Topic: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).
Replies: 16
Views: 311

Re: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).

@Roland, Reading the example (headstart) that was given me I do sort of understand what is going on. Got it compiled in my own ISE (14.7) version here. Created a UCF file to have the signals a little more arranged. Creating the PCB now (in Kicad) , I’m here in Italy for another week, Tuesday I will ...
by bprosman
Fri Aug 09, 2019 12:23 pm
Forum: hardware
Topic: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).
Replies: 16
Views: 311

Re: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).

One point of caution, though the code above compiles OK I don't have the hardware so it's untested :)
No problem :-) I take that part.
by bprosman
Fri Aug 09, 2019 12:01 pm
Forum: hardware
Topic: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).
Replies: 16
Views: 311

Re: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).

@Phill,

Many thanks !!
This will give me a nice headstart.
XC9572 is not an issue as it is there in a 44pin (SMD) version so not too much of a footprint.

Kind regards, Bram
by bprosman
Fri Aug 09, 2019 7:27 am
Forum: hardware
Topic: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).
Replies: 16
Views: 311

Re: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).

Can you post the complete schematic you are trying to re-engineer? Sure , here it is, a memory mapper "stolen" from a few other designs : I hoped to fit it in an XC9536 or XC9572 (44 pin). As mentioned, I found some VHDL definitions of the chip here : https://github.com/Idorobots/upnod-card0117-tn6...
by bprosman
Fri Aug 09, 2019 6:14 am
Forum: hardware
Topic: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).
Replies: 16
Views: 311

Re: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).

Hi Dave, First of all thanks for the swift reply. I did found some VDL sources : https://github.com/Idorobots/upnod-card0117-tn64/tree/master/vhdl/src For me this looks understandable. Next thing (to learn) is to how to connect "Real signals" (eg an address line) to a VHDL "74ls139" for example. Tha...
by bprosman
Thu Aug 08, 2019 11:30 am
Forum: hardware
Topic: Discrete logic (TTL) into a CPLD (XC9536 or XC9572).
Replies: 16
Views: 311

Discrete logic (TTL) into a CPLD (XC9536 or XC9572).

Currently I am experimenting (again) with Xilinx CPLD's. In the past using Altera there was a library to build a schematic using TTL replacements from a library. That was easily translated into an EPM3064. In Xilinx I actually dont find this functionality, I am looking into "translating" a schematic...
by bprosman
Mon Jul 22, 2019 9:20 pm
Forum: acorn atom and system
Topic: Atom2k15 boards on Ebay. **** DO NOT BUY ****
Replies: 3
Views: 442

Re: Atom2k15 boards on Ebay. **** DO NOT BUY ****

They still have 135 of these in stock :
https://shop.trenz-electronic.de/en/TE0 ... n-IDC?c=12

That would work with my adapter PCB, just for the die-hards.

viewtopic.php?f=41&t=12954&p=221943&hilit=ice+t#p221943
by bprosman
Mon Jul 08, 2019 8:47 pm
Forum: hardware
Topic: Addres Decoder calculator. Who knows one ?
Replies: 1
Views: 251

Addres Decoder calculator. Who knows one ?

Years and years ago I used to have a DOS program which was an "Address decoder calculator". You filled in the address range and the calculator gave you the required Address lines as well as the logic equations (that could be fed into a PAL/GAL etc.). But cant find it anymore in my archives. I can do...
by bprosman
Sun Jul 07, 2019 10:32 pm
Forum: acorn atom and system
Topic: ICE T65/Z80/6809
Replies: 658
Views: 56973

Re: ICE T65/Z80/6809

Today the ICE-T65 was a great help again to get a board running it's 1st program, test the memory and memory decoding.
Processor (program) is nicely looping and debugging.

WHAT A GREAT TOOL !!!

Next step to get some I/O done.
IMG_0542.jpg
IMG_0543.jpg
by bprosman
Sat Jul 06, 2019 9:09 pm
Forum: acorn atom and system
Topic: AtomSID
Replies: 35
Views: 2506

Re: AtomSID

Also curious in (if any) quality differences between a SwinSID and a FPGA-SID
by bprosman
Sat Jul 06, 2019 12:08 pm
Forum: acorn atom and system
Topic: AtomSID
Replies: 35
Views: 2506

Re: AtomSID

I personally can't.. maybe Dave Hoglet could (give his view).
by bprosman
Sat Jul 06, 2019 11:25 am
Forum: acorn atom and system
Topic: AtomSID
Replies: 35
Views: 2506

Re: AtomSID

What would be the smallest FPGA that would just hold a "SID" ? Well maybe with some additional address decoding.
by bprosman
Mon Jun 24, 2019 1:28 pm
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 201
Views: 7720

Re: Atom Video to HDMI Adapter

Got an e-mail from Farnell that they run out of stock for the TI version of the LM319 and then its over (220 in stock).
They recommend ON Semi.

@Dave , any experience with that brand ?
by bprosman
Mon Jun 24, 2019 9:06 am
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 201
Views: 7720

Re: Atom Video to HDMI Adapter

Let me check , but let's build PCB first. Hoping to have the parts arrived this week. They add a little on to the price but at least you can get stuff in a couple of days Well , I checked that earlier this week but a 8051 core processor was 7 Euro , versus 4 Euro directly at Farnell (VAT excluded). ...
by bprosman
Sun Jun 23, 2019 5:54 pm
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 201
Views: 7720

Re: Atom Video to HDMI Adapter

Hi Roland,

Thanks for the offer, I have as well but the Dutch Farnell doesn't seem to have it in their catalog.
I can check the UK site.
by bprosman
Sun Jun 23, 2019 11:51 am
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 201
Views: 7720

Re: Atom Video to HDMI Adapter

Tried to order the case but the companies I found thus far charge 15...20 GBP for shipping to NL.
Thats 3..4 times the costs of the box.
So will look for a "Continental replacement".
by bprosman
Sat Jun 22, 2019 5:42 am
Forum: hardware
Topic: ATOM Restored, Space-bar needed
Replies: 26
Views: 843

Re: ATOM Restoration, Space-bar needed!

I do have a desoldering station which already cleared 2 earlier boards, so if you need some help.
by bprosman
Fri Jun 21, 2019 4:00 pm
Forum: hardware
Topic: ATOM Restored, Space-bar needed
Replies: 26
Views: 843

Re: ATOM Restoration, Space-bar needed!

Seeing ugly single sided IC socketd :(
Definitively would remove / replace those one day.