Smonson's slow H4 build

Topic for users to share their building progress.
Post Reply
User avatar
Smonson
Posts: 708
Joined: Sat Oct 28, 2017 10:21 am
Location: Canberra, Australia
Contact:

Smonson's slow H4 build

Post by Smonson »

I just got my PCB on Thursday and I must say it's very exciting! The quality of these boards is incredible.

I mentioned "slow" in the subject because I don't have most of the stuff I'm going to need to assemble my board, and I'm not even ready to begin.

Unlike most of you guys, I've got a DIP64 HC CPU (16MHz) which I'm hoping can be installed in one of the expansion sockets, instead of a PLCC CPU. My donor chipsets are PLCCs. The SIMM socket price is ...not ideal. I think I'm going to chuck half a meg of DRAM on a veroboard to plug it into the falcon RAM socket instead of giving money to Big-SIMM-Socket, those corrupt bastards.

I don't think I'm going to bother installing some of the non-essential sockets like the cartridge port. Too lazy to desolder it!
User avatar
Icky
Site Admin
Site Admin
Posts: 3986
Joined: Sun Sep 03, 2017 10:57 am
Location: UK

Re: Smonson's slow H4 build

Post by Icky »

:welcomewave: to the H4 party @Smonson

CPU in one of the expansion sockets should be fine and an interesting test for the board.

Looking forward to seeing your HDMI board on the H4 :)
User avatar
Smonson
Posts: 708
Joined: Sat Oct 28, 2017 10:21 am
Location: Canberra, Australia
Contact:

Re: Smonson's slow H4 build

Post by Smonson »

Now that everyone's finished their boards, it's time for me to start:
h4-1.jpg
h4-1.jpg (404.52 KiB) Viewed 10306 times
I got all the SMTs on there.

With the benefit of everyone else's hindsight, I cut three tracks underneath the video DAC before soldering it in.
2020-01-11.jpg
2020-01-11.jpg (387.91 KiB) Viewed 10306 times
User avatar
Icky
Site Admin
Site Admin
Posts: 3986
Joined: Sun Sep 03, 2017 10:57 am
Location: UK

Re: Smonson's slow H4 build

Post by Icky »

Smonson wrote: Sat Jan 11, 2020 9:41 am Now that everyone's finished their boards, it's time for me to start:

I got all the SMTs on there.

With the benefit of everyone else's hindsight, I cut three tracks underneath the video DAC before soldering it in.
Nice! - This is partly why I haven't built the second board yet as doing these neater fixes with hindsight as you say makes for a neater board.

I shall probably do the same when I build the second one.
User avatar
PhilC
Moderator
Moderator
Posts: 6016
Joined: Fri Mar 23, 2018 8:22 pm

Re: Smonson's slow H4 build

Post by PhilC »

That does look like a good idea. Unfortunately I'd soldered two of my boards at the same time with the SMT stuff
If it ain't broke, test it to Destruction.
User avatar
Smonson
Posts: 708
Joined: Sat Oct 28, 2017 10:21 am
Location: Canberra, Australia
Contact:

Re: Smonson's slow H4 build

Post by Smonson »

Quick question, what is the ROM part? Does the H4 use a "44-pin JLCC JEDEC" compatible pinout?
User avatar
PaulJ
Posts: 1568
Joined: Sun Apr 08, 2018 1:14 am
Location: USA

Re: Smonson's slow H4 build

Post by PaulJ »

Smonson wrote: Tue Jan 14, 2020 3:32 am Quick question, what is the ROM part? Does the H4 use a "44-pin JLCC JEDEC" compatible pinout?
I'm using AT27C4096-55JU-T Mouser# 579-AT27C4096-55JU-T
User avatar
Smonson
Posts: 708
Joined: Sat Oct 28, 2017 10:21 am
Location: Canberra, Australia
Contact:

Re: Smonson's slow H4 build

Post by Smonson »

Thanks @PaulJ. Gosh they're not cheap for a OTP, are they :shock:
User avatar
kodak80
Posts: 370
Joined: Sat Oct 21, 2017 1:14 am
Location: Brisbane,QLD Australia
Contact:

Re: Smonson's slow H4 build

Post by kodak80 »

@Smonson I have used the OTP ones but have also used HN27C4096ACC-10 chips which seem to work fine on stock H4.
https://www.ebay.com.au/itm/1pcs-HN27C4 ... 2103003184
Atari Falcon 030 | Atari 1040 STE | Atari 1040 STFM | Atari 1040 STF | Kryoflux & Supercard Pro Flux boards
Creator of the Atari ST Review magazine archive: https://www.chillichai.com/atari-st-review
User avatar
Smonson
Posts: 708
Joined: Sat Oct 28, 2017 10:21 am
Location: Canberra, Australia
Contact:

Re: Smonson's slow H4 build

Post by Smonson »

Thanks for that @kodak80, that's much more like what I expected for an old-style EEPROM.

I never cease to be amazed that you can buy 32GB of flash for $10 and yet a chip with less than a meg on it can be the same price or more.
Post Reply

Return to “MONGREL H4 USER BUILDS”