Before actually procuring the chip, it is important that you modify THE SERVANT to suit your own preferences. Please refer to appendix B.
Once your servant has been modified, it's time to make a chip. THE SERVANT is designed to be programmed into an EPROM (Erasable Programable Read Only Memory) chip. To do that, you'll need an EPROM programmer. Any 64/128 programmer will do.
You may even attempt transferring THE SERVANT code to MS-DOS using Big Blue Reader and use a PC equipped with an EPROM burner card. In that case, please note that the PRG file produced by THE SERVANT (using CONTROL/+) has two bytes in the beginning which holds the start address of the file, which is not an actual part of THE SERVANT code. You must get rid of those two bytes in one way or another. You may load THE SERVANT into a word processor or text editor and use it to delete the two first bytes. Alternatively, the EPROM burner software might have the ability to skip a given number of bytes in the beginning of the object file.
The chip itself must be a 27256. Program it using the EPROM programmer as described in your EPROM programmer manual. The 27256 come in two versions; One for 12.5 Volts programming voltage, and one for 21 Volts. Often, the programming voltage is printed on the chip itself. If in doubt, try programming using 12.5 Volts first. Then, if it won't work, try 21 Volts. If you don't have an EPROM programmer yourself, some member of a local user group might have one. If you wish to buy an EPROM programmer, please find the address of Jason Ranheim in appendix F.
If you can't find an EPROM programmer, just send a 27256 EPROM to the author. There will be a turnaround fee; please refer to the license terms printed in the file named "read me". The EPROM will be returned with THE SERVANT programmed into it. Please read appendix B on customizing THE SERVANT and describe as closely as you can how you want your SERVANT to be configured. I will read and follow your instructions! You may, at any time, return your SERVANT EPROM if you wish to alter THE SERVANTs configuration. The same turnaround fee as above will apply.
INSTALLATION:
THE SERVANT can be installed in the internal ROM socket in any 128 or 128D, in a ROM cartridge, or even inside the Commodore 17xx series Ram Expansion Units. I will include instructions for each of the above.
Opening your computer tend to make you both nervous and eager at the same time, and you may tend do become absent minded. Therefore, read the whole installation guide and troubleshooting section, BEFORE opening your computer. What it all boils down to is that if you feel confident, you are more likely to avoid blunders.
COMMON TO ALL C128 MODELS:
Turn off your entire system. Unplug all cables (even keyboard cable on 128D), and take your computer to the kitchen. Computer chips are sensitive to static charges (but not as sensitive as often claimed), and the kitchen is a room where static normally don't occur. No carpets, and a fairly high humidity. Don't wear clothes made of synthetic materials. Wear wool or cotton. You need a large clean working space, at least twice as wide as your computer. You'll probably be surprised how much space your computer takes up in disassembled condition. Then put on your surgeon's gloves, scalpel in hand, and dive into it. It is of paramount importance to your success that you take your time and use good common sense. When unplugging connectors, note (using pencil and paper) where they belong and their orientation, just to be on the safe side. Marking the connectors might also have the side effect that it increases your confidence of you're a bit nervous in the outset.
Tools required:
A medium sized phillips screwdriver
A pair of flat-nosed pliers (for the flat 128)
You may also consider:
Pencil and paper
A small flat screwdriver or chip pulling tool
A pair of tweezers (to pick up lost screws)
Contact cleaning spray (ozone friendly!)
A chip pin straightening tool
A chip insertion tool
An ashtray, egg carton or similar to hold the screws.
Opening the "flat model" Commodore 128:
1) Turn the computer up-side down, and remove the six screws.
Turn the computer back the right way. There are some small plastic hooks on each side near the top of the keyboard which still holds the two halves together. Pull the two halves apart in the REAR LEFT CORNER just enough so you can get your fingers in-between. Then, using brute force, pull the two halves apart.
On the left, there is a small connector with three wires attached to it that goes to the power LED. Unplug it.
3) Now, turn the keyboard over towards the right. You will notice that it hangs in the keyboard wires. There's no need to unplug those.
3) Remove the seven screws around the edges of the of the metal shield. The screw at the front right has a grounding strap from the keyboard which you must detach temporarily. Some computers also has a screw roughly in the middle of the shielding (near the RF connector). The shield is also held down by a number of metal tags around the edges. You'll have to bend them aside. You may even break them off as they serve no useful purpose. You may also have to bend aside the tags surrounding the plastic stalk in the middle.
4) In some 128s the shielding is even soldered in place at one point. If that is the case, bend the shielding up and aside enough so that you can access the rear left portion of the circuit board.
5) Now, please refer to the chip insertion section below.
Opening the 128D portable (Plastic case with carrying handle):
1) Turn the computer up side down and remove the four screws.
2) Grasp the computer firmly with both hands (so it won't fall apart uncontrollably) and turn it over.
3) Remove the cover by lifting it slightly at the back and then pulling it back slightly.
4) The lid is attached to the power lead to the main circuit board, so you'll have to turn the lid over and lay it down to the left of the computer.
5) Pull out the disk drive lever
6) Remove the three screws just behind the front cover at the top.
7) Lift the front panel up and away from the base.
8) Remove the disk drive circuit board, removing the five connectors and the two fixing screws.
9) There is a wire from the circuit board to the main shielding which will have to be removed.
10) Slide the circuit board to the left and lift it away.
Remove the power supply. Undo the four screws and remove the connector in the far right corner. Remove the wire attached to the disk drive unit. Lift the power supply away.
11) Now, read the installation instructions below.
Opening the "new" 128D (Metal case with no carrying handle):
1) Look at the rear and find the three largest Phillips screws that are fastened to the top lip on the case on the back. If you are lost, do step 2 first, and then return to this step.
2) Turn the computer upside down. There are two screws to undo on the underside. One very close to the cassette port and one on the other side (near the power light).
3) Grasp the computer firmly with both hands so that it won't fall apart uncontrollably, then turn it the right way up.
4) Now the hardest part. Grab the top of the case and slide it back from the rest of the 128D till it stops (just short of an inch movement or about 2 cm). Pulling from the top lip where the three first three screws were seems to work best. Now lift the cover straight up and off of the 128D. Notice how the cover slides off of the four tabs which fits into the four slits on the top cover (two on each side).
5) Now, read the installation instructions below.
INSTALLING THE CHIP:
If you have a flat 128 or 128D portable, you will soon notice the empty socket on the rear left. In the "new" 128D however, the socket is located 2.5 inches from the FRONT and 2.5 inches from the left. In either case, the socket is marked U36. That is the internal ROM socket.
Before insertion, you will probably have to straighten the pins of the chip. On a fresh new chip, the two rows of pins are normally pointing slightly apart. You will need to straighten them so they are completely vertical. You may hold the chip in both ends, and lay one row of pins flat down on the table. Then roll the chip slightly so that the pins become straight. Repeat the process with the other row of pins. DO NOT bend the pins so that they point inwards. Alternatively, you may use a pin straightening tool if you have it.
Now, insert the chip. The chip has a notch at one end which must point towards the front of the computer. All the other chips in the vicinity is oriented the same way. Check that each and every pin goes into a hole in the socket. Push it down.
A common problem when the chip is first inserted is that one or more of the pins don't make proper contact with the socket. This is due to oxidization of the hitherto unused socket contacts. Malfunction will result. To remedy the problem, lift the EPROM slightly in both ends and then push it down again. Repeat this a couple of times.
COMPUTER RE-ASSEMBLY & TESTING:
Follow the disassembly instructions for your computer in reversed order. Connect the power cord and monitor (and keyboard if applicable). Don't connect other peripherals yet. Turn on your monitor and let it warm up for about thirty seconds. Then turn on your computer. THE SERVANT main menu should appear on the screen. If THE SERVANT do appear as expected, power down and connect your peripherals. Enjoy!
Help! It doesn't work:
Don't despair (yet). Take a deep breath and calmly follow the test procedure below that fits your problem in a step by step fashion.
No screen display:
1) Check the power lights on your computer and monitor. Do they indeed shine?
2) Check that the computer monitor are using the same screen mode and is properly hooked up to each other.
3) Try removing THE SERVANT chip.
4) If the system is still dead, the computer itself must have become faulty. Hard luck! Shake the computer and listen for a rattling sound. There might be a metal object (maybe a screw) which makes a short circuit somewhere. Also, you may check the few wires on the circuit board to see if they have come loose at the solder points. Also check that everything is re-assembled properly. This goes especially for the 128D portable.
The C128 power-on message appears, the system then hangs up:
1) Press the reset button. If that doesn't help, turn off the computer, wait for approximately 15 seconds, then turn back on.
2) If you have connected the serial cable, power down and unplug it. If the computer works now, try to locate the peripheral which causes the interference. This should not happen with any Commodore brand peripherals; Printer interfaces are probably the most likely to cause problems although every effort has been put forth to avoid it. I should note that if you are using a 1581 disk drive, it will hold back THE SERVANT for a moment. Please write the author and explain your problem if you find that a certain peripheral is causing problems.
3) If none of these suggestions will cure the problem, read the section below.
The computer powers up just like it did before the ROM installation, THE SERVANT menu appears, the system then hangs up or goes heywire, THE SERVANT works, but hangs up or goes heywire after a while:
There is some problem with the chip. It may be faulty, which is not very likely, or one of more of the pins are not making proper contact with the socket.
1) Inspect the chip where it sits. Is it indeed oriented with the notch towards the front of the computer? If not, turn it around and test. Surprisingly, ROM chips often survive being inserted the wrong way around.
2) Remove the chip, check that no pins are bent out of shape which may account for the malfunctioning. Carefully straighten any bent pin(s), then re-insert the chip.
3) If all pins were OK, then clean the socket contacts using a contact cleaning spray or fluid. Re-insert the chip and test.
4) Try bending the two rows of pins on the chip slightly closer together.
5) If nothing works, send the chip to the author for testing. Please describe the nature and symptoms of the problem and everything you have done to fix it. If possible, please state your SERVANTs version number.
THE SERVANT works OK, except that it crashes when using the Datamaker and some Disk Tools sections:
1) The chip might have been programmed using the file "the servant.bin". This file lacks a part which is essential to THE SERVANT's operation when working in ROM. THE SERVANT must be programmed using the file "the servant.mod" as created by pressing CONTROL/+ on the main menu.
2) The file used to program the EPROM was saved to disk using BSAVE, ML monitor S command or by other means. While this method MAY produce an error-free file, it is very unreliable. Same cause, effect and cure as 1) above.
MOUNTING THE SERVANT INTO A CARTRIDGE:
THE SERVANT will work without modification in a cartridge. However, this solution is not recommended unless you have a very good reason to choose it. Mounting THE SERVANT in a cartridge will tie up your expansion port, and as soon as you remove the cartridge your computer becomes plain stock again. THE SERVANT in a cartridge will not work switched on at the same time in conjunction with other cartridges (except 17xx REU's) using an expansion board. If you can, mount THE SERVANT in the internal ROM socket!
The cartridge you wish to use must be able to hold a 32K ROM chip. Some cartridges can be reconfigured using jumper wires or switches to hold different kinds of chips. The cartridge manufacturer should supply the cartridge with instructions on how to set up the cartridge. PLEASE NOTE: There is a significant difference between 64 and 128 mode cartridges. Make sure that you get a 128 type. Some units has jumpers or switches to configure the cartridge for 64 or 128. Using a 64 mode cartridge will make the computer always power up in 64 mode. However, a 64 only cartridge can be modified for use on a 128. Here's how: Hold the cartridge the right way up with the connector towards you. On the top side, locate contacts number 8 and 9 counting from the left (counting 1-2-3 not 0-1-2 and remember to count missing contacts). Cut the leads connected to those two contacts, and cut the two contacts apart if they are joined together. The cartridge should now work in 128 mode. For troubleshooting, the same will apply as for the internal ROM installation. However, the cartridge won't work if it's improperly configured.
MOUNTING THE SERVANT INSIDE THE 17xx SERIES RAM EXPANSION UNITS:
This modification is only for the confident soldering iron slingers among you. This explanation will therefore be very brief. Please note that the DMA chip inside the REU is extremely sensitive to static charges. When opening the REU, you will see the outline of a chip printed on an otherwise empty part of the circuit board. Just outside the outline there are two rows of holes. Mount a LOW PROFILE 28 pin IC socket into the holes and solder it in place. Mount THE SERVANT chip into the socket with the notch the same way as shown on the outline printed on the circuit board (notch to the left, towards the big REC chip). You'll also need to alter a jumper or two on the REU's PCB. There are two versions of the Commodore REU, and the altering of jumpers are different. The two REU types are distinguished by the big REC chip close to the edge connector:
A) REU with SQUARE REC chip: Change over J2 (it actually looks like I2). The jumper looks like three tiny metal squares. Normally the middle one and the one furthest away from the edge connector is interconnected by a tiny strip of metal. You must cut the existing connection and connect the middle square to the one closest to the edge connector using a drop of solder.
B) REU with RECTANGULAR REC chip: You'll need to connect two jumpers: One is marked J5, connect the two metal squares. The other is marked J2 and consists of three metal squares. Connect the middle one to the left one; the one marked 27256.
Re-assemble the REU and test. PLEASE NOTE: If you mount THE SERVANT into the REU you will no longer be able to use your REU and other cartridges switched on at the same time using an expansion board.
IMPORTANT NOTE about cartridge & REU installation: Due to that THE SERVANT chip (when mounted externally) and the QBB cartridge use the same memory space, the QBB features won't work in this configuration. Any attempt to use the QBB and THE SERVANT switched on at the same time using a cartridge expander board will probably make THE SERVANT malfunction as well.
