- The LaST Upgrade -


Fitting Guide by nukebloodaxe

July 30, 2016 - Last updated August 5, 2016


32Mhz Booster in it's original packaging
The 32Mhz STE Booster in its original packaging.
Booster Kit Bag
A better view of the bag and its contents, awaiting the moment to escape all over your work area.
Kit pieces Laid Out
The contents of the Kit laid out, the PLCC socket is hiding behind the GAL. In shot we can see the wire for soldering to various areas on the STE motherboard, the SILS [5], the strips of pins [3], the 32Mhz 68000 CPU, the board itself, and a GAL.
PLCC revealed
I flip the GAL over, and reveal the PLCC.
Determining Pin strip length
I determine the length of pin strip required by positioning a strip roughly in the holes [yes, I know I could count them, but this is likely to have less mistakes.]
Cutting the pin strip
I cut the strip at the given position with a craft knife.
Pin Strips Cut
After repeating this procedure 4 times for each type of required strip I end up with 4 rows of 8 pins, and 4 rows of nine pins.
Soldering Temperature
I personally work at 300 Degrees C, and use rosin cored 60/40 solder with a no-clean flux. This allows me to work at 2 seconds per pin, minimizing heat exposure to the components.
Note on Temperature
Be careful, some equipment is overzealous when reheating the tip when the temperature drops during the soldering process itself. This particular unit is fine, but if you have a sudden 10 degree rise it can be enough to make Vias suddenly burn off the board.
Sil Positioning
I am soldering the SILS first, I position then one at a time, making sure that the Dot is next to pin 1.
SILS soldered
I pre-flux the pads and pins with no-clean flux, and ensure the SIL is in the correct position. I then solder alternating pins, until done.
SILS Topside
In this shot the SILS have all been soldered in place. Note the one to the right, this is what can happen if you solder sequentially, instead of soldering the fist and last pins first. In this case it does not matter, as it is well below the height of the PLCC socket.
Inserting PLCC socket
I have inserted the PLCC socket into its area, note the orientation of the socket, and where the squared-off edge is.
The PLCC Pins Awaiting Soldering.
The PLCC pins are now ready to be prepared for soldering, I apply no-clean flux to the pins and Vias.
PLCC Pins Soldered
I solder the pins, starting with the corners first. It is extremely important to make sure the PLCC socket is flat against the board before soldering them.
PLCC Pins After Cleaning
The area is cleaned with IPA, and the result mopped up with a tissue. Due to the amount of pins there will be some tissue residue left.
PLCC Socket After Soldering
The PLCC as seen from above, it is soldered in position and flat against the board.

The GAL is extracted from the protective foam, at which point I note it is trying to form an M, and the pins are spaced much wider than the target area for the GAL. After much cursing I apply just the right amount of pressure against each side of the GAL, bending all the pins at once so that they can fit in the target pin holes.

(All new IC's have the pins bent at a angle - you have to straighten them to fit on the PCB - placing the IC on its side and bending all the pins inwards a fraction is all it takes to align them - exxos)

GAL In Position
The GAL is now in position, note the orientation of the groove towards the PLCC socket
GAL Pins Soldered
I preflux the pins and pads with no-clean flux. As this is the first IC I have ever soldered, I say a small prayer and then work at a rate of one pin every 1.5 seconds, making sure I'm working on pins that are as far away from each other as possible.
GAL Post Soldering
The GAL as viewed from above, remember it is important not to use too much solder, you are aiming for electrical connectivity, not to have it dripping down the IC's legs like it's a candle.
GAL Pins Cleaned.
I clean the GAL pins with IPA, using a tissue to mop up the resultant mess. If you look at the PLCC socket pins to the left, you'll see that it is difficult to clean those properly, mainly because there are so many.
STE CPU Area Minus PLCC Socket
The PLCC socket for the original CPU has been cut to pieces, and the bits carefully taken away from the pins [as per exxosuk's guide at http://www.exxoshost.co.uk/atari/last/removal/index.htm.] This particular example looks like strands of natural silver growing in their native environment... it's not supposed to look like that, and I have forgotten to trim the pins before taking the socket away.
STE CPU Socket Trimmed
This what it is supposed to look like, ensure you have a pair of long-nose pliers with a decent grip, you'll need it for pulling the pins out during desoldering. I also recommend a bamboo toothpick, this is for the holes that will not clear with either desoldering wick, a desoldering gun, or a vacuum pump and soldering iron. What you do is you put the pick through the hole on the top of the board, and melt the solder with the iron from the other side. The pick will push out the solder, and not stick. The result is that you have a small hole just the right size for the pins to fit through.

This particular job above is completed following this guide: http://www.exxoshost.co.uk/atari/last/removal/index.htm

Booster Board Modification For STE Blitter Socket.
The STE board I am using has a Blitter in a PLCC socket. In order to ensure there is no interaction between this and the booster board I am cutting a small piece of the PCB away. Use this image as a guide if you wish to do it yourself. The tool I used for this is a Citadel Miniatures Plastic cutting saw, which works very well for this process; look at the cleanliness of that cut!

(Had me worried there! Though it was to chop off investigative little fingers! - exxos)

Closeup of Modified Board
A closeup just in case you want to take measurements against your own.
Wire preparation
I have compared the wire against the TOS upgrade, and cut a section that will reach from the CE pad to pin 6 of the TOS switcher; when the booster is in final position. I have also prepared and pre-tinned two pieces of wire I will use for the 32/8Mhz switch.
Wires in position
I personally prefer to solder the wires from the rear of the board, So I put each wire through its relevant hole, and solder them in position. I preflux with no-clean flux before doing this, and clean the resulting joint with IPA. Having two different coloured wires on the switch is for personal preference.
Soldered Wires From Above
When wires like these are soldered from the read of the board the result top-side is much more pleasant looking, again, this is personal preference.
Another Shot of Soldered Wires From Above
A better shot of the switch to board link.
Pin Strips in Position
I spend quite a while putting the strips of pins into their correct holes, and then shuffling the booster board around until they all fit through the booster board. However, something is wrong, the board is tilting weirdly. I look between it and the main board, and find the red coloured SILs on the board are "interacting" with the pins on the bottom of the booster board.

I remove the board, and carefully cut all the pins that are hitting the SILs, and then put the board back in position. I now preflux the pins with no-clean flux, and solder the corner pins first.

All Booster Pins Soldered and CE to Pin 6 Soldered.
All the pins leading into the board are now soldered, sticking with the outside first, followed by the inside pins. The result is then cleaned with IPA, and mopped up with a tissue.

I also solder the wire leading from CE on the STE Booster board to the TOS switcher, on Pin 6 [counting from the left] closest to the TOS Rom.

Soldering Switch Ground Wire
I then solder the ground wire from the switch to the corner hole of the earthing strip along the motherboard edge, prefluxing this is a good idea as it absorbs heat quickly. Note the odd looking holes on the base of the board where the booster pins have yet to be soldered? There are three of them, and they required the bamboo toothpick trick.
Ground wire From Above.
The ground wire is placed in this position, as it will not be covered by the STE metal shroud, and you can route it through the gap.
Booster Motherboard Pins Soldered
I preflux the pins and pads with no-clean flux, and then solder the pins quickly, making sure I do not use excessive amounts of solder.
Pins and Board Cleaned
I clean the pins and board with IPA, cleaning up the resultant mess with a tissue. I then check that all pins are correctly soldered to the board. For those pins that are not, more solder is added.
The Booster in position with all wiring and without CPU
The booster with all the wires in position, we will be adding the CPU next, but take a moment to see how the wire has been positioned that leads to U405.
Clk 32 Wire to U405, pin 4 from the right.
The wire leading from the clk 32 pad is soldered to pin 4 of the IC located at U405. I pre-fluxed this pin with no-clean flux, pre-tinned it, and pre-tinned the clk32 wire before soldering it to pin 4. As a result the joint is very clean and tidy.
CPU in position and Booster Complete
Once the CPU has been placed into its socket, note the position of the dot, the booster is complete, and we are now ready to perform testing.
Adding Exxosuk Power Supply
We add the power supply [a nice exxosuk unit] and a monitor. It is time to cross our fingers, and hope that it does not catch fire.
Boot TOS 1.62
No fire... looks stable
TOS 2.06
Well, it's running, time to box it up and get it home.
Shroud Fits
With the booster being low, due to the cut for the Blitter, the metal shroud fits nicely. I do, however, recommend insulating the Booster and TOS switcher from the shroud. In my case I use cut to size pieces of paper.
Assembled at Home
The keyboard is added, and a CosmosEX [by Jookie, see here: http://joo.kie.sk/?page_id=384 ] fitted to the board. I use a PS4 controller for the games, and a standard laser mouse. The screen is a DELL model featuring a composite port, and I use a monitor to composite port cable which also has RCA stereo out; as if I didn't already have enough RCA ports on the STE.

The power supply in this case is an FSP Gold 650 Watt ATX unit. I have attached a molex splitter to one of its lines, and wired both the plugs to the wires from a standard STFM power supply plug. A floppy connector from the same supply goes to the CosmosEX, reducing the total power load on the STE motherboard.

The plastic bag is being temporarily used to insulate the switches from the surrounds and one another.

Boot to desktop, TOS 1.62
I take out the pizza that has been cooking in the oven, and place it to one side of the STE.
I then proceed to ensure that the booster is in 32Mhz mode, TOS 1.62, and boot the machine. It works, which is encouraging.
GEMBench testing
I run GEMBench, this is the insiital screen before the tests are run. I start all tests and begin eating my pizza.
GEMBench Results TOS 1.62 - 32Mhz
Well, its certainly working, lets continue to the next stage.
TOS 2.06, 32Mhz
TOS 2.06 boots, and we're away.
GEMBench Testing, TOS 2.06
This is the initial screen before the test runs, I am now half way through my pizza.
GEMBench Results, TOS 2.06 - 32Mhz
I'm not complaining about these results, it'll certainly help me with some heavy lifting that I'm interested in; probably porting IronSeed to the STE, if possible.

One Tidy Machine and an Empty Plate
I'm very happy with this kit, as it does what it says on the tin, as it were. I also need to put that empty plate away. Have fun all of those of you attempting to do the same; the kit, not eating the pizza.

(We never found out what the toppings were on the pizza.... - exxos)


Original page http://imgur.com/a/FuPeV