Fred Astaire’s Doppelgänger

Oh crap… This blog is getting dusty. Anyway, let’s get started!

I compared the Street Fighter 2 Champion Edition joypad routine with the one from HuDK. One of the most interesting thing is that SF2 performs an extra joyport read after reading the 5 joypad states in order to check if a Multitap (PI-PD003) is there. If the returned value is $F0, we have a Multitap.

Is there a way to detect how many joypads are plugged? What about the other multitaps

Hopefully a Twin Tap and a Twin Commander magically landed on my desk for some time (thanks Adoru).

Let’s start with the Twin Tap. It’s a 2 ports multitap. Unfortunately there’s no way to detect available joypads or a 2 ports multitap.

Anyway! This multitap has some interesting peculiarity. If you check the you’ll see that there’s not 2 but 3 ports and a 3 positions selector switch. Why is there a third connector and a selector switch? I’m afraid we’ll never know.

The selector switch changes the joypads order. This means that the joypads plugged in the Twin Tap will appeared at a different position in the joypad read routine. Here’s a table with the switch positions and the joypad “positions”.

Switch position123
Joypad #0ACC
Joypad #1BCC
Joypad #2CAC
Joypad #3CBC
Joypad #4CCA

As the C port is hidden (unless you are a sneaky hacker), the joyport value will always be $FF (no buttons pressed).

Conclusion: At the time of writing this post, only the Multitap (PI-PD003) can be detected and we can’t detect if a joypad is plugged. I don’t have much hope for the Joy Tap 3, the Battle Tap or the X-HE2, but who knows…

Higher resolution images can be found here

Harry Dumper and the order of the Griffin

The Magic Griffin is a game copier. From the menu and the case, it seems to have been made by a taiwanese company called Front Fareast and JSI.
I don’t know if the Front Fareast listed on wikipedia is the same [link]. And I’ve found nothing about JSI.
About the hardware. You plug it in the Hucard slot and the joypad port. Oh I forgot, you can only use it on a PC Engine/CoreGrafx. On the front you have a standard Hucard slot and 2 joypad ports. Only the right one is working. I don’t know what’s the left one is used for. There are 2 parallel ports on the right. One for an external floppy disk drive and another one labeled COM port. I only tested the floppy disk.

Magic Griffin Mugshot Top view
Side connectors
Front View


What’s inside?

An Altera chip, a Motorola chip, some RAM, some TTL chips and a UV EEPROM (on the onther side). I haven’t identified the chips yet.
So what happens when you power it on? Well you see this:

It may work like the other flash cards (TotoTek PCE Pro, Krizz Everdrive). This means that it acts like a standard Hucard. But some special addresses are used to communicate with the special hardware. For example the Everdrive can access the SD card via some addressess that are mapped to the SPI registers. I pretty sure the code is hosted on the UV EEPROM.
About the menu.


RUN FILE: Run a file from the floppy disk.


RUN IC CARD: Run the Hucard.
Unfortunately I was unable to run any card. It either tells me that there’s no Hucard or it will freeze. This surely comes from oxidized card connector.

SAVE IC CARD: Save Hucard to floppy disk.
It’s the menu that would have sent you to jail in the 90’s 😀 You name the file, press I and it will start dumping the Hucard on the floppy disk. Unfortunately the controls are awful. Pressing RUN will spit a whole lot of chars. Same for SEL, it’s more likely that it’ll delete the whole filename. You can’t write a single char. So you’ll end up with filenames like ‘ssssooooolll’ or ‘bbbbooommbbb’ 🙂
As I said before I was unable to run any Hucard. Despite the fact that it seems to have dump the game, I was unable to run any of the game I’ve dumped. I’ll check the dumped files as soon as I get my hands on an USB Floppy drive. But I’m pretty sure I’ll have a bunch of 0xff.


RENAME FILE: Rename one of the file on the floppy disk.

DELETE FILE: Delete a file from the floppy disk.


FORMAT DISK: Format floppy disk.
You can either format a HD (1.44M) or DD (720K) floppy drive. Be carefull, it’ll start formatting the disk once you enter the menu.


That’s all.
I’ll try to clean/fix the connector. And once I receive the USB floppy drive I’ll check the dumped files and verify which filesystem the disk was formatted.
The coolest stuff will be to dump the UV EEPROM. So if someone knows how to safely read it, I’ll be more than pleased to hear it.

Note: This was originally posted on the PC-Engine dev forum [here].

You see this? This… is my boomstick!

(10/23/2012) WARNING! As Tomaitheous pointed out, there’s a problem with this board! Please refer to comments for more informations.

Yeah a new post!

Some years ago (more like a decade than a year), I bought a Turbo Stick. It’s the standard 2 buttons stick for NEC PC Engine console. Unfortunately the stick makes an awfull squealing nose. Forget 1 life run with this plastic beast. After 5 minutes all I wanted to do was to use it as a soccer ball. According to the Wataru’s PC Engine hardware list, 4 six buttons sticks were released. They are not small and given shipping costs I decided to build one. So I bought a stick and some buttons from Sparkfun. Later a friend gave me a Sanwa stick and buttons.

There are several places on the internet where to find PC Engine pad schematics. The main source are Emanuele Bettidi‘s pad schematics, PCE Wiki, NFG PC engine/TG 16 article. I first built a 2 buttons circuit with no auto fire. But there are a few games that requires a 6 buttons stick (Street Fighter 2 for example). The Avnue Pad 6 comes with auto fire and slow mode. The later is a particular ugly hack. The slow mode is acheived by toggling the pause rapidly. It’s as if you drank too much coffee and go berserk on the RUN button. Here are the guts shots and schematic of an Avenue Pad 6. I spent hours trying to make PCB board in Eagle for the “complete” version (with auto fire and slow mode). I didn’t find a local source for the DTC114Y. A replacement was found on the interweb. It was told that this component can be replaced by a 2N3904 and 2 resistors. This is rather straightforward if you look at the DTC114Y datasheet. Anyway, in the end I didn’t liked the way the board looked. The most logical step was to remove the rapid fire and slow mode (schematic). And by the way, I think I’ll never use slow mode and barely ever used auto-fire.

Here are the current version of the schematic and pcb board:

Here’s a 3d view of the nearly version of the board (made with WebGerber)

I need to add mounting holes in the board. Make some board. And last but not least, build the enclosure!