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PCB Target Manager

Introduction (1st January 2005)

Inspired by cgfm's work on interfacing Sega pcb's to PC's using a USB link I decided to try something similar but more general. The easiest way I could think of was to overlay some kind of read port into the rom space of a game - that way you get access to the address & data bus but without needing to know any details such as custom cpu pinouts. It also works with any type of cpu (68000, ARM, Z80, etc). I briefly investigated a USB link to PC but decided on parallel port as it's cheaper and simpler. Some TTL logic is used to interface the parallel port with the rom socket. With a link in place all that is needed is software on both PC and the target platform to communicate over the link.


With an interactive link from PC onto a target pcb it is easy to probe protection devices so that they can be emulated. It is also easy to figure out specific graphics effects or unknown registers and test timing.


The target software consists of a 'kernel' for each target CPU type and a 'driver' for each target platform. So, the game Rohga would use the 68000 kernel and a specific driver to implement the game specific parts. A game like Fighter's History would use the ARM kernel and specific driver.

The PC side software consists of a console application (the 'Target Manager'):

As well as allowing you to read/write in the address space of the target CPU you can put together script files of multiple commands, or upload binary data. By combining upload & execute you can run programs on the target cpu to test things like timing which are hard to do interactively.


Software and hardware schematic will be avaliable for download after I tidy everything up a little.


Here is a version of device using 27c040 (512Kb) size roms installed on a Taito F3 Landmaker pcb. The device has also been successfully tested on Rohga Armour Attack (Data East) and Mutant Fighter (Data East) so far.

Landmaker target Device on Landmaker pcb Device

Data East custom protection chip '104' has been analysed allowing Rohga & Schmeiser Robo to be emulated. Some Taito F3 graphics effects have also been analysed though the emulation hasn't been updated yet (VRAM layer blending, new palette effects, per tile scaling).

Schmeiser Robo Rohga Armour Attack Rohga Armour Attack


Next on my list is to analyse the protection device in Fighter's History - this requires a version of the device to be built that can be used with 27c4096 roms (16 bit, 40 pin). After that I'll probably look at the protection devices in Hacha Mecha Fighter (NMK) and Cup Soccer (Seibu) as I have those pcbs. (Nb: As always, I give no time frame for actually doing any of this!).

(Request: Does anyone have any 27c4096 eproms they don't need? I have zero spare so I'd have to erase some off a working game).


Feel free to send any feedback or suggestions to 'pcbtm at'.