Thursday 24 December 2015

Day 24 - Atari ST PC with intel i7

This is day 24 of the Advent Calendar of USB keyboards. No, not Ruud Gullit sitting on a shed as predicted, but an Atari ST.
But this is no ordinary Atari ST. It has one of these inside.
Yes, that's an i7 4790K. This is going to take a while, so are you sitting comfortably? Well, it all started with a request for an Atari ST USB keyboard kit, and turned into quite a project. The owner asked if I could install a PC inside the ST, sure not a problem.
He sent me the donor ST and the bits to go inside. The i7 was a little gruntier than I was expecting (atom, Raspberry Pi, the NUC I used on the 800XL PC etc.).There were two main issues to think about here, power and heat.
The Atari ST has an internal power supply, that wouldn't be powerful enough for the new purpose, but it would be good to keep the mains input and power switch, and keep everything internal.
The initial thinking was to use a 12V power brick and something like a Pico PSU which plugs into an ATX connector and just requires a DC input. They only went up to 120W, and the owner was thinking they would need more. (processor TDP=85W, plus RAM, SSD, USB peripherals etc.)
We settled on a miniITX board that had a built in DC-DC and only required a single 19V DC input from a laptop power brick. This is the Asus H81T. All the connectors are along one side and not very high, and it looked like they would line up perfectly with the three D connector slots on the ST case.
There was one problem with that, it left the CPU under the keyboard, so there wouldn't be enough height for a cooler, especially one for an i7.
I did look at a few options, including using an old after market GPU heatsink, bent around to fit on the processor, but it wasn't really going to be viable.
Rotating it around, in both positions where there was sufficient height for the stock intel fan, all those connectors faced inwards. Not ideal, but when it came down to it, not many of those would actually be required. In the end, only the DVI out needed to be extended to the rear panel.
Time to put it all together. I rewired the mains input to feed a 200W laptop power brick, that should be enough power. The motherboard manual was very vague on power requirements, I only knew it was 19V as that was the label on the silkscreen, no actual statement of requirements. In testing, it didn't draw more than 60W, so that should be more than enough overhead.
I left the cable full length, so it could be replaced at a later date with another standard model. The connector on the end was a standard 2.5mm DC jack, so I made up a short lead to connect to the 2 pin header on the motherboard.
Under the power supply plate, I fitted two USB sockets, wired to the internal USB header on the mainboard.
The DVI connection was extended to the rear panel using a short cable, the shortest I could find that would reach. This was DVI-I, so a VGA adapter could still be used if needed.
On the left there, you can see the USB keyboard controller, wired to a single USB header on the mainboard with a short USB lead.
This connects to the Atari ST keyboard with a short cable with mating pins. It's been quite a 3D spacial puzzle fitting all this stuff in, but I like a challenge.
One of the reasons it was easy to go with rotating the board is the audio outputs on the mainboard were not being used. The owner had supplied a USB audio device. This has 4 phono plug for the inputs and outputs, but he wanted two 1/4" jacks, so I made up short leads for those and fitted the sockets on the side of the case.
I kept the original USB lead and plugged it into one of the spare USB ports on the board. Also plugged in there is a USB MIDI adapter.
This originally had 5 pin DIN plugs on to connect directly to an instrument. The ST originally had two 5 pin DIN sockets on the side, so I've rewired the USB MIDI adapter to sockets where the originals were.
The RAM and mSATA SSD are mounted on the mainboard, so no external drives to connect. A DVD-RW drive was requested, but I just couldn't find a space to squeeze it in.
I would normally have added quite a bit of hot melt glue to ensure it all holds in place, but the owner wants to strip it down when they get it and spray it black.
The processor is under the vents on the top of the case, and the side of the case was already cut out to fit a larger floppy drive, so there should be reasonable airflow. The modern i7 processors are a lot more efficient and run far cooler than those of the past. Compare the stock cooler here to the massive Noctua NHD-14 cooler on my old i7 (I've still got that somewhere, anyone want to buy an i7 950 for some old school overclocking?)
Are there it is, an Atari 520STFM running Windows 10, with a little help from an intel i7.
This is the last day of the Advent Calendar of USB keyboards, hope you've made it to the end. Thank you to those that have stuck with me. Time for a bit of a rest now; normal service will resume in the new year.


Update:
A new dedicated version of the Atari ST USB keyboard controller used in this build is available from my Tindie Store.


2023 Update

USB Keyboard Controller Kits are available from my Sell My Retro store:

Wednesday 23 December 2015

Day 23 - VIC20 USB keyboard with USB hub

This is day 23 of the Advent Calendar of USB keyboards. Today, a Commodore VIC20 USB keyboard with USB hub.
These keyboards are all built to order, so I'm happy to take requests for changes. On this occasion, I was asked if I could fit a USB hub in the side (instead of USB joystick ports).
No problem. It took a while to find a suitable USB hub with the right spacing between ports, but I found a nice 4 port one. The metalwork is actually from a Commodore 64, as the VIC20 only had one  joystick port.
This was fitted inside and hot melt glued in place. Three ports on the outside (one blocked by the metalwork), and one inside for the USB keyboard itself. Leaving a single USB lead from the back of the case.
In use, just plug your USB devices into the side of the keyboard.

Tune in tomorrow to open the final window on the Advent Calendar of USB keyboards. Will it be Ruud Gullit sitting on a shed?

2023 Update

USB Keyboard Controller Kits are available from my Sell My Retro store:

Monday 21 December 2015

Day 21 - Atari ST USB keyboard kit

This is day 21 of the Advent Calendar of USB keyboards. Today, an Atari ST USB keyboard conversion kit.
I've been asked to build a few of these or assist with conversion projects on Atari STs. The conversion is easier than something like the Amiga 500, as it uses a standard serial protocol, albeit at the slightly usual baud rate of 7812.5.
The serial cable from the keyboard is unplugged from the ST and plugged into the lead from the USB keyboard controller. The cable is polarised to connect only one way.
The USB keyboard controller is mounted to the case at an appropriate position, either with the USB socket facing outwards, for USB keyboard use, or mounted inside if you are adding a computer of some description.
Most Atari ST keyboards includes two 9 way D joystick ports which can be accessed from the underside of the Atari. I understand the early smaller 520ST with no internal power supply or floppy drive has a different arrangement, but I have not been able to test this controller with one of those.
These will appear as USB joysticks alongside the USB keyboard, so you can use original Atari / Commodore joysticks.
The Atari ST USB keyboard conversion kit consists of the controller board, mountings and USB cable.

Tune in tomorrow to open another window on the Advent Calendar of USB keyboards.


Update:
A new dedicated version of the Atari ST USB keyboard controller is available from my Tindie Store.


2023 Update

USB Keyboard Controller Kits are available from my Sell My Retro store:

Tuesday 15 December 2015

Day 15 - Commodore Amiga 500 Pi2

This is day 15 of the Advent Calendar of USB keyboards. Today, an Amiga 500 USB keyboard with USB joystick ports and integrated Raspberry Pi2.
This follows on from the previous post on the Amiga 500 USB keyboard. The new board is designed to be built with different options, the main choices being for use as a USB keyboard with an external computer, or with an integrated computer.
In this case, it is built as a USB keyboard and dual USB joystick with an internal USB header, and a DC-DC converter to generate a stable 5V supply for a Raspberry Pi.
As with the other USB keyboards with integrated Raspberry Pi, I am moving to using 12V in and generating the 5V supply from that. The DC-DC is rated to supply up to 2A at 5V, it is fairly efficient so doesn't get very warm, and drawing less than 1A from a 12V supply at full load. In normal operation, it's only using about 20% of that, so lots of overhead
It is easier to find a 12V 1A supply than a 5V 2A one, and is no longer reliant on the quality of the external supply to keep the Pi happy.
The board sits in the same place, with two 9 way D connectors for the joystick ports, but this version has a 2.1mm DC jack for the 12V in. As before there is space for a mode switch if required.
The Raspberry Pi 2 is modified as usual, one dual USB port is removed and replaced with a single USB port, and the spare port is wired to a 4 pin header for the USB keyboard controller. Power in is wired directly, bypassing the microUSB connector.
This fits into one of the slots on the rear of the Amiga 500, with the HDMI extended to it's side. So in what was the parallel printer port, you have RJ45 LAN, three USB ports and next to it the old power connector has the HDMI out.
Add back the original Amiga keyboard and a USB mouse, and it's ready to go.
The Amiga emulator is not supplied with a kickstart ROM image, as that is technically still under copyright, so I read in the kickstart ROM from the damaged board.
Ready for some thorough testing. Let's go.....
You can order a Commodore Amiga 500 USB keyboard kit from my Tindie Store (the version without the power input)

Tune in tomorrow to open another window on the Advent Calendar of USB keyboards.

2023 Update

USB Keyboard Controller Kits are available from my Sell My Retro store:

Thursday 10 December 2015

Day 10 - Spectrum +2 USB keyboard + USB hub

This is day 10 of the Advent Calendar of USB keyboards. Today, a Spectrum +2 USB keyboard, but one with a difference. The buyer asked if I could fit a USB socket inside the tape deck, so they could charge their phone.
No problem, I always like it it when someone comes up with something I hadn't thought of. I was looking at fitting a USB socket inside, but there wasn't really anywhere one could be mounted to. Then I remembered a 'novelty' USB hub I had bought a while ago, I think they have now been discontinued (but so has the Spectrum +2).
This is the same size as a cassette tape, but is a 4 port USB 2,0 hub with 4 USB ports on the edge. It wasn't designed to be put into a cassette deck as doesn't have holes for the various parts that stick into the open edge of the cassette. But it does actually fit and has rotating reels in the centre. It won't close due to various parts of the cassette drive mechanism below.
I had a Spectrum+2 cassette deck (sorry 'datacorder') that was faulty and had already been partly stripped for parts, so I removed some more. I had to remove the capstan, pinch rollers and some plastic guides to get it to close, and the playback and erase heads to avoid fouling with the USB hub when play is pressed.
You can press play and it won't damage the hub. Nothing will happen, but you can still press the buttons if you want.
When closed, it just looks like there is a tape of games in. Or a tape of anything - I found this in a Spectrum +2 last week, wouldn't load for some reason.
Inside there was a cutout on the back where the record tab sensor was positioned, this wasn't quite in the right place for the mini USB connector on the hub.
With that enlarged, the miniUSB is plugged in and the wire is led out of the back of the case.
The rest of the keyboard is my normal Spectrum +2 build, with the keyboard controller mounted on the back of the keyboard.
This is the grey +2 model, which has a different keyboard membrane to the later black +2A, +2B and +3 Spectrums. This one is still an 8x5 matrix, like the original Spectrum and Spectrum+.
With the keyboard stripped down for cleaning, you can see the parts of the multilayer matrix. The first part is a two layer membrane for most of the keys.
On top of that is another two layer membrane for the special keys only (space is at the top of the picture).
All back together, the two layers are joined by conductive pads on the left hand side, held down by 4 screws.
I've left the USB keyboard and the hub separate, each with their own USB leads coming out of the case. The hub one could be connected to a USB port, or to a mains USB charger.
The power LED is wired to the USB keyboard controller, so will light up when it is active. When you want to charge you phone, just press eject to open the hub and plug in your normal charging cable.

Tune in tomorrow to open another window on the Advent Calendar of USB keyboards.

2023 Update

USB Keyboard Controller Kits are available from my Sell My Retro store: