A4000TX ATX Amiga motherboard

Hi I am having difficulties programming U714 with a TL833-II-programmer. All the rest of the GALs are fine but not U714. Anyone else experienced anything like this? Have used several different chips.

Thanks,

Bjorn
 
Hello. I now start working on the A4000tx.
It will be my first big project. I've never soldered as much as I'll have to with this one.
But I can't get the file to work with pcb-explorer.It is a very useful tool.
I use windows 10 and firefox.
I would greatly appreciate your help to make it work.
Thanks.
 
Hello. I now start working on the A4000tx.
It will be my first big project. I've never soldered as much as I'll have to with this one.
But I can't get the file to work with pcb-explorer.It is a very useful tool.
I use windows 10 and firefox.
I would greatly appreciate your help to make it work.
Thanks.

I followed the instructions referenced here, but using a Linux container on my notebook. Worked a charm :)

Good luck with your build.
 
Hi all, everyone with problems running PCB-Explorer running under Windows 10, install Safari Browser 5.1.7 for Windows and simply use this to open PCB Explorer. It works and will solve your problems. Woz.
 
It's fantastic. Safari does the job just fine. Without any special configuration.
Thanks a lot Woz.
 
Last edited:
Hello. I have little left to finish soldering the smaller components and start with logic gates and customs chips.
But I am having trouble locating some mouser references with pcb explorer. Could it be equivalences?

863-NRVB120VLSFT1G (4 units)
610-CMPT3904E (4 units)
512-MMBFJ113 (2 units)
621MMBD7000HC-7-F (5 units)

What is it called in the pcbexplorer?
Thanks a lot.
 
hello. I have little left to finish soldering the smaller components and start with logic gates and customs chips.
But i am having trouble locating some mouser references with pcb explorer. Could it be equivalences?

863-nrvb120vlsft1g (4 units)
610-cmpt3904e (4 units)
512-mmbfj113 (2 units)
621mmbd7000hc-7-f (5 units)

what is it called in the pcbexplorer?
Thanks a lot.


863-nrvb120vlsft1g - 1N5817
610-cmpt3904e - 2N3904
512-mmbfj113 - MPF102
621mmbd7000hc-7-f - 1N4148
 
I am looking for 54pin edge connector.
And one 72pins simm socket (mine has had an accident ;)).

Has anyone to sell?
---------------------------

found both.
 
Last edited:
A Big Thank You

A Big Thank You

I am pleased to report that my A4000TX build booted first time!


Having said that I did struggle programming the AVR, but after a lot of reading and some experimentation on a spare I found I needed to reduce the bitclock period for the USBasp to communicate with the AVR. This was a bit of a steep learning curve for me because my only previous experience with AVRs have been on development boards which are preconfigured with a bootloader.


You’ll see from the picture I still have work to do finishing off adding the connectors. Then I need to source a case, mouse and keyboard... in beige of course.


A big thanks to hese for creating and offering this great project and to screemo and ObjectiveD for their advice which gave me the confidence to take on this project.


A4000TX_Test-min.jpg
 
Floppy Drive Options

Floppy Drive Options

Hi,

What floppy drive options/configurations are supported by the A4000TX:


  1. Two Amiga floppy drives?
  2. Can we mix Amiga HD & DD drives like with the A4000D?
  3. Two PC floppy drives? Assume use twist cable?

Just checking before I invest in diffcult to find and expensive floppy drives.

Thanks in adance.
 
When I asked Hese about floppy drive options for my Rev1.0 A4000TX this was his reply

The motherboard was designed for one floppy drive only.
It's possible to add support for the second floppy drive but you would need to add some jumper wires.

I dont know if it's different on the Rev 1.1
 
When I asked Hese about floppy drive options for my Rev1.0 A4000TX this was his reply

The motherboard was designed for one floppy drive only.
It's possible to add support for the second floppy drive but you would need to add some jumper wires.

I dont know if it's different on the Rev 1.1

Thanks and thats a shame. I had hoped to add another drive or Gotek. Interested to know what modifications would be required to add a second drive.

In better news, I'm happy to report I have found a great case for my A4000TX. I've also sourced a very tidy CDRW for £7 and was given an old PC floppy drive which had a black fascia which I resprayed to match the case. I'm very please with result.

More to do such as RTG card and an accelerator for starters :D

20210405_155412.jpg
 
Hi!

I've unfortunately sold all my LCD's capable of 15 kHz so I'm forced to connect to my lab TV with SCART from the A4kTX.

Will it be sufficent to connect RBG + grounds + Composite + Ground and 5v via resistor to pin 8 & 16 ? (Function & fast switching).
Happy with picture, not looking for any quality :)
 
Hi!

I've unfortunately sold all my LCD's capable of 15 kHz so I'm forced to connect to my lab TV with SCART from the A4kTX.

Will it be sufficent to connect RBG + grounds + Composite + Ground and 5v via resistor to pin 8 & 16 ? (Function & fast switching).
Happy with picture, not looking for any quality :)

Hi Kavven,

Take a look at Ian Stedmans excellent site for a detailed RGB to Scart wiring diagram and lots other useful info. It worked a dream for me.
 
Hi!

I've unfortunately sold all my LCD's capable of 15 kHz so I'm forced to connect to my lab TV with SCART from the A4kTX.

Will it be sufficent to connect RBG + grounds + Composite + Ground and 5v via resistor to pin 8 & 16 ? (Function & fast switching).
Happy with picture, not looking for any quality :)

Hi Kavven,

Take a look at Ian Stedmans excellent site for a detailed RGB to Scart wiring diagram and lots other useful info. It worked a dream for me.

Thx!
Will change the connections to 8 and 16. Apart from that it should be ok.

Thx again, never seen that site before. :)
 
Last edited:
Had a success startup with DiagRom (no chip or fastram) but after adding U455 & U456 I lost reset signal..

Still missing some other chip though. But curious if the reset got lost because of some solder misstake that got triggered because of adding U455 and U456 or if its normal and I should keep on adding components...? :/
 
Back
Top Bottom