I picked up a non-working Laser War a few months ago, with heavy battery damage to the original MPU board. Not wanting to invest too much time on a basically hopeless board, I picked up an allegedly working rev 3 MPU off of Ebay (pulled from a LW3).

As you may know, a rev 3 MPU board will not work directly in Laser War, for a few reasons (27C256 ROM vs 27C512; extra pins on C12, etc.). Anyway, I'm currently running through the "conversion" process laid out by an old DE service bulletin but am not having any luck getting fully through the boot process--or so it seems.

Basically what I'm seeing is that the board goes through the basic self check portion of the boot successfully (+5/PIA flash to Blank/+5 solid) but then basically nothing happens (nothing on the display, no sounds, no controlled lights, etc.)...However, I can see ghosting in some inserts if, e.g., I hit the coin switches, start button, etc., so it seems like *some* software might be running???

I verified that my installed EPROM is valid (matches V1 ROMs on Stern's site)...

Set jumpers using info from the following:
http://www.sternpinball.com/downloads/sb6.pdf
http://www.pinwiki.com/wiki/index.php?title=Data_East/Sega#CPU_Jumper_Settings

Set on: J4 (32KB ROM), J5A (no clue), J6A (single ROM?)
Set off: J5 (64KB ROM), J5B (no clue), J6B (dual ROMs?)

The pinwiki guide said to set J7A instead of J7B, but I skipped that setting as my original Laser War MPU had J7B set. I have no idea what J7x controls, however...

Surely I've screwed something up here...Anyone have any ideas?

Should clarify: Game says "Laser War" at start up, but that happens even if the MPU isn't present.

Also--looking again it appears that J4/J5 may control single or dual ROM configuration...I thought I'd read elsewhere that J4/J5 controlled addressable ROM size...Ugh, the documentation for the jumper settings is awful.

This is where I read that J4/J5 control installed ROM size:

http://techniek.flipperwinkel.nl/desega/index2.htm#testroms

"CPU Jumpers.
Early DataEast games (Laser War to Batman) may require the CPU board to be rejumpered to use a 27512 EPROM at position 5C. The two jumpers used in all DataEast/Sega games are J4 and J5. These two jumpers dictate the maximum size of the CPU EPROM at position 5C. Games Secret Service to Batman were released with a 27256 EPROM as the largest EPROM usable at position 5C, and jumper J4 installed and jumber J5 removed. Star Trek 25th Anniversary to Batman Forever were released with a 27512 EPROM as the largest EPROM usable at position 5C, and jumper J5 installed and jumper J4 removed. Use jumper J5 installed and J4 removed when utilizing the diagnostic test 27512 EPROM at position 5C. Jumpers are discussed in the section titled Getting Started: Different Board Generations, CPU Jumpers. "

Yes--plus J4 instead of J5 to config for 27c256 instead of 27c512

I ran the test rom from http://home.scarlet.be/~fb054529/dataeast/edataeast.htm. Outputs from all PIAs appeared to be correct and in general the test program appeared to be running successfully per the instructions, though I forgot to do the RAM check portion (was late last night). I will run through the tests again on my test bench to double check.

I popped in a 27C512 with the Laser War ROM image doubled up (used copy /b command in windows command prompt). I get the same result as I did with the 27C256...The CPU partially boots but appears to hang...A thought I had was perhaps the software is performing some hand shaking with the sound or display boards and the software is written such that it will block until the hand shake is made...Anyone else seen/heard of this on older Data East title? I haven't seen any DataEast "circuit theory"/start-up doc out there so I'm not sure what the boot sequence should be or if there are any by-design blocking mechanisms in the software.

Anyone have any other good test ROM recommendations? Looks like there may have been another one out there but it's pretty scarce--found it on vpin forums but haven't tried it or found doc for it.

Thanks doctor_pinball--I'll look into the RAM differences. I actually hadn't checked the type of RAM on the MPU as I was assuming the RAM type was the same through all rev 3 boards and the DataEast service bulletin calls out the RAM differences between Rev1/2/3. (i.e., their prescribed jumper settings would address the difference)

I ran through the Leon flavor test ROM again (http://home.scarlet.be/~fb054529/dataeast/edataeast.htm). All PIA tests pass and the RAM check passes.

I tried the original DataEast test ROM ("detest"/"de_test") that I downloaded from the vpin forums but the PIA light gives me no flashing. I'd run this on my test bench instead of in the machine--perhaps the program blocks if it's not hooked into the machine???

These are the instructions I found elsewhere that I believe are for the same ROM:
"The test EPROM for DataEast/Sega CPU boards has the following functions. When the Test EPROM is installed into a CPU board and power applied, the CPU will perform power-up self tests and then immediately go into burn-in cycles with no intervention. It is not required that the Test button be pressed in order to initiate burn-in cycles.

The power up self-test will check major components on the CPU board and flash the LED as each one appears normal. If any fail, the LED will stay on. The tests consist of a checksum test of the ROM and read/write test of the RAM and the PIA's. The PIA test will NOT check both sides of all PIA's since certain PIA ports are designed to be inputs and the loading on those ports will determine the data seen by the CPU. However, those ports designed to be outputs will be written to and read from in order that basic go/no-go functionality can be checked.

Flash Chip Location Tested
----- --------------------
1 C5 (ROM checksum) 2 D5 (RAM read/write) 3 5F (PIA1 solenoid read/write $2100) 4 8H (PIA5 switch read/write $3002) 5 11D (PIA2 lamp read/write $2402) 6 11B (PIA3 display2 read/write $2802) 7 9B (PIA4 display1 read/write $2C02) 8 7B (PIA6 sound read/write $3402)

The burn-in test will cycle through the solenoids, lamps, display and sounds like the present burn-in, with the following exceptions.
- The solenoid cycling will go through all the solenoid matrix positions.
- The lamps will go through all the patterns of rows and columns, as well as individual lamps; any shorts or opens will be easily seen on a test set lamp matrix board.
- If any matrix switches become closed, the lamp patterns will stop for a time. The lamp(s) corresponding to the matrix position of any closed switch(es) will be turned on. This faciliates testing of the switch matrix. A short time after the switch matrix becomes clear the lamps will go back to patterns. This also means that if any switch matrix position appears closed on power-up, the corresponding lamps will be turned on after the power-on self tests for a visual indication of where problems are located.

Neil Falconer, DataEast 1/6/93"

Looks like the 6264 and 2064 (latter called out by service guide) are compatible.

Jumper table for future reference

DECPUJUMPTBL.jpg

Update

I tried moving the board from my bench to inside the machine with all cables connected. Leon's test ROM had (unless I overlooked something) all flashers and solenoids firing sans two (left flipper and kick back solenoids). No controlled lights were operating. I also ran DataEast's official test ROM. All 8 of the core MPU tests pass, however shortly after the burn in test appears to hang after switching the relay off for the pf GI (hear the relay click on the power supply -> pf GI is off)...I'm not sure if this is due to the software hanging because it's in an older/incompatible machine or what. I also don't see any controlled lights here either--not sure if this is normal.

Question: Does anyone know if I should be seeing any of the controlled lights (insert lamps) firing during Leon's test or early on in the DataEast test?

At this point it appears the v3 MPU (from LW3) is *at least* "mostly" good and there is maybe some undocumented incompatibility with Laser War, *OR* Laser War's software is hanging for some reason unknown to me...Potentially due to some external component not responding.

I'm not sure what the overall state of the machine was (basically trashed when I got it)...Anyone ever see DataEast software hang due to an external component failure? (I'm wondering just in case this was common to their software...Even the official test ROM appeared to hang/block when not installed in the pin.)

That would be great if you had additional info. The bulletin from dataeast calls out that it's possible--perhaps it's incomplete, however.

The original MPU was trashed with extensive damage to components along the ground plane around the entire board. I may have been able to fix it, but elected to go the less stressful route of using a 'new' clean board. My original board was actually rev 2 but with a smaller rev 1 RAM chip.

Update: Success--I discovered and repaired a short on the MPU and now it is fully booting.

The steps that I outlined above--which are fully documented in the linked Stern/DataEast service bulletin--are correct for converting a rev 3 board into a rev 1/Laser War compatible board.

Now on to the next problems: Dead display and ball trough not sensing balls (can't start a game as ball search kicks in when pressing the start button).

I should also mention: The additional steps referenced by thedefog are for converting a *Sys11* MPU, which requires several more steps of a higher degree of difficulty. If I had to do this again on a known working rev 3 board set it would easily take me less than an hour to do the Laser War conversion--very simple.

Excellent--high voltage is good so another board would be great even for debugging purposes. PM me your info and I'll paypal over the funds. Thanks!

Consolidated v3 conversion steps:

1) Follow the core of the conversion guide in bulletin #6: http://www.sternpinball.com/downloads/sb6.pdf
....a) Remove jumpers J5B and J6B at location D8
....b) Install jumpers J5A and J6A at B7 and D7
....c) Add 3 pins to CN3 (top-right of board)
....d) Remove the EPROM from the socket at position B5 (if any)

2) Install Laser War ROM (http://mirror2.ipdb.org/files/1415/Data_East_1987_Laser_War_ROMs_V1_00.zip)
....a) *IF* using 27512 (64KB) EPROM
........i) Remove jumper J4 and install jumper J5
........ii) Double up Laser War ROM using the copy /b command in the Windows' command prompt
............1) copy /b LWARv1.C5 + LWARv1.C5 LWAR64.C5
........iii) Burn ROM (LWAR64.C5) to a 27C512 or 27512 and install into socket at position C5
....b) *IF* using 27256 (32KB) EPROM (not recommended)
........i) Remove jumper J5 and install jumper J4
........ii) Burn ROM to a 27256 or 27C256 and install into socket at position C5

I went with option 2.a as it permits me to easily swap in test ROMs such as Leon's ROM or DataEast's test ROM. Use these ROMs for extensive diagnostics of your v3 MPU board.
1) Leon's ROM and instructions: http://home.scarlet.be/~fb054529/dataeast/edataeast.htm
2) DataEast's in-houes test ROM (search for detest.zip if link is broken): http://www.vpforums.org/index.php?app=downloads&showfile=811

Instructions for using DataEast's test ROM:

"The test EPROM for DataEast/Sega CPU boards has the following functions. When the Test EPROM is installed into a CPU board and power applied, the CPU will perform power-up self tests and then immediately go into burn-in cycles with no intervention. It is not required that the Test button be pressed in order to initiate burn-in cycles.

The power up self-test will check major components on the CPU board and flash the LED as each one appears normal. If any fail, the LED will stay on. The tests consist of a checksum test of the ROM and read/write test of the RAM and the PIA's. The PIA test will NOT check both sides of all PIA's since certain PIA ports are designed to be inputs and the loading on those ports will determine the data seen by the CPU. However, those ports designed to be outputs will be written to and read from in order that basic go/no-go functionality can be checked.

Flash Chip Location Tested
----- --------------------
1 C5 (ROM checksum) 2 D5 (RAM read/write) 3 5F (PIA1 solenoid read/write $2100) 4 8H (PIA5 switch read/write $3002) 5 11D (PIA2 lamp read/write $2402) 6 11B (PIA3 display2 read/write $2802) 7 9B (PIA4 display1 read/write $2C02) 8 7B (PIA6 sound read/write $3402)

The burn-in test will cycle through the solenoids, lamps, display and sounds like the present burn-in, with the following exceptions.
- The solenoid cycling will go through all the solenoid matrix positions.
- The lamps will go through all the patterns of rows and columns, as well as individual lamps; any shorts or opens will be easily seen on a test set lamp matrix board.
- If any matrix switches become closed, the lamp patterns will stop for a time. The lamp(s) corresponding to the matrix position of any closed switch(es) will be turned on. This faciliates testing of the switch matrix. A short time after the switch matrix becomes clear the lamps will go back to patterns. This also means that if any switch matrix position appears closed on power-up, the corresponding lamps will be turned on after the power-on self tests for a visual indication of where problems are located.

Neil Falconer, DataEast 1/6/93"

Yes--the consolidated steps (in my last post) represent the way to successfully convert your working v3 board (and how to run two different diagnostics programs).

I ended up getting the red Xpin display set (which is completely amazing) and fixing the ball trough issue. I'm currently down to just a handful of minor issues (weak left flipper, overly-sensitive "A" switch and a non-working switch on the ramp).

Thanks for the guidance everyone!

He needs to have a way to set the jumpers mentioned above...My original board was actually rev2 with less RAM and 'modified' jumpers (factory configuration).

A 'regular' Rev 2 wouldn't work OOB, similar to a rev 3.

Worst case scenario you may be able to cut traces and run jumper wires. I would say go rev 3 unless they can guarantee a non-hack conversion path.

Note that you also need the extra 3 pins on CN3. Make sure they have that or your display won't work right.