exxos's Atari, Amiga & retro forum

The H5 will be the successor to the H4 board. Primarily the H5 will have all the fixes and patches that the H4 needed it can be read about in this thread..https://www.exxosforum.co.uk/forum/viewt ... =73&t=2801

A lot of talk about the future of the motherboard is in this thread here https://www.exxosforum.co.uk/forum/viewt ... =73&t=2764

So people don't get confused about what is going on.. The H4G (H4 revision G) is the SMT version of the H4F (H4 revision F which people have). The H4G is the last in the series but that board will not actually be produced.. It is more of a wrapping up the H4 series so we can build upon that to generate the H5 series.

As discussed *somewhere* The H5 will see a "replacement" of the flashy clock socket Which will have IO 5V to 3.3V translators to make flashy clock socket a 3.3V bus. They also hope to place a similar socket to the left which will give us 2x 3.3V bus sockets.

Why are we doing this 3.3V bus ?
Because it makes not much sense to put level translators on every single addon board which will ultimately plug into the motherboard. We don't have any plans currently other than to convert flashy clock to a pure 3.3V version. It will basically pave the way that add-ons for the H5 boards will be cheaper to produce, and cheaper to buy for H5 users. I also mention similar in this thread https://www.exxosforum.co.uk/forum/viewt ... =73&t=2755 . The bottom line is we need a 3.3V bus to develop addons on, so this will be done on the H4. The other expansion ports will remain 5 V for the time being.

Other changes on the H5 will see a reduced number of jumper headers. Primarily these were there to split clock lines and such for the 16MHz mod. I will not go into all that again, but the bottom line is, it is a dead-end road, and we need to move towards the FPGA solutions and push 32MHz and up. so a lot of related jumpers are simply being removed now.

I have also decided to go with the PLCC MFP. So the DIP one will be removed. The PLCC one will be soldered directly onto the board at some point during assembly.

There is a couple of other little ideas floating around of things to add, but it is too early to say at the moment if anything else will be added or changed.

Sounds awesome 😁

exxos wrote: 20 May 2020 22:41 I will not go into all that again, but the bottom line is, it is a dead-end road, and we need to move towards the FPGA solutions and push 32MHz and up.

I'm very saddened by this. A "like Atari had done it" higher bus speed mode with new available video modes is, IMHO, more interesting than simply a faster ST. Personally it's why I'm interested in the remake, but it's not my call.

/Troed

troed wrote: 20 May 2020 23:20 I'm very saddened by this. A "like Atari had done it" higher bus speed mode with new available video modes is, IMHO, more interesting than simply a faster ST. Personally it's why I'm interested in the remake, but it's not my call.

It can never be a reliable mod, the wake up states mean there's a 1 in 4 chance of it even booting. Not to mention it was a right PITA to get it running on the Alpha. I'm not going to produce a machine which needs to be reset several times just to get it to boot. But it still stands thats that project can go nowhere afterwards. A 32Mhz bus would surely be a lot better ? double the video bandwidth of 16Mhz.

Small update. @Icky added in the 3.3v stuff etc and handed the files back to me to do some tidying ups and a few tweaks which are now done. One thing I am going to add is a simple 3.5mm DC jack on the back to power things like ultrasatan. I'm not doing anymore changes to it now. Really I just wanted a updated H4 with a 3.3v bus to aid in development.

Next step is I have to put JLC part numbers on all the parts and I will probably have to write a script to convert eagles BOM to a format JLC can use, so this will keep me busy for a while yet.

Just as a tiny bit of news, I have started today adding in the JLC part numbers into the PCB BOM.

Once I actually know what the cost is of the parts and assembly, I actually get a price for the boards..

Converting the PCB BOM to JLC BOM took a bit of work.

JLC BOM is like this..


PCB BOM..


So I created a quick script to convert the formats.

The first pass simply gets rid of the unwanted columns..Then formats data as JLC basically expects it...


There does not seem to be any information to say exactly what is required, so I then wrote another script to amalgamate all parts using the same part number in the same line as the JLC example..


Anything without LCSC part number is ignored and the result is something like this..


Next I have to write another script to convert the XY locations into JLC format...


EDIT:

just realise there is a mistake In my output script, but nobody is likely to notice anyway :lol:

First attempt :roll:




There seems to be another problem now...

When you order 5 or 10 pieces PCBs, you can get 2 PCBs assembled by JLCPCB and solder the remaining PCBs yourself.

But there is only a option for 5 or 2 pcs.. so no clue what its on about... It mentions <30pcs on the page as well.


@terriblefire You any idea what its on about ?

EDIT:
Nevermind, I only had 5pcs selected for the PCB :roll:

Well :headbang: :cussing: :cussing: :cussing:

Cannot use more than 10 kinds of Extended parts for each order.

How things are looking..

4 of the LS chips will have to be left off and the 3.3V regulator :roll: There isn't much else I can do with the limit of 10 "extended parts". At least those chips are lowest count on the board so less soldering.