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MAME and paddle controllers

03/05/2010 – 21:02

I just got a Sega Master System paddle controller working with the Retro Adapter. It works perfectly but there is a compatibility problem with some MAME games I had not anticipated.

I tried to use it with Arkanoid. That game uses a spinner control which can rotate endlessly clockwise or anti-clockwise, unlike a paddle which has a set range it can cover (typically 360 degrees). MAME does not support absolute positioning for spinner controls (or dials as it calls them). The Sega controller reports back a position from 0 to 255 but MAME needs left/right pulses as you would get from a decoded optical Gray code sensor of the type commonly used in mice.

Apparently absolute positions are usable with mice so I will try to set the controller up in that mode tomorrow.

This kind of problem seems to be common with emulators.

By mojo | Posted in Retro Adapter, electronics, hardware, software | Comments (0)

CA-42 as USB to RS232 converter 5V signal compatibility

26/04/2010 – 00:23

The Nokia CA-42 cable is well known as a cheap USB to RS232 converter. You can get them on eBay for about �1. One thing that was not clear from most of the articles about it is how tolerant the signalling voltage can is.

According to the datasheet for the IC used in the CA-42 (a Prolific PL2303HX) it supports both 3.3V and 5V signals. The CA-42 provides 5V and 3.3V and the PL2303HX outputs 3.3V on it’s TX line, but putting 5V on the RX line is specifically mentioned in the datasheet as being safe.

As for the power lines the 5V is probably direct from the USB port, less the amount used by the PL2303HX, so it’s likely to support a few hundred milliamps. The current limit of the 3.3V line is unknown but most likely in the 50-100mA range at best.

By mojo | Posted in electronics | Comments (0)

AVR / electronics quick reference sheet

23/04/2010 – 18:31

I am working on a quick reference chart (cheat sheet). It’s by no means done but a post over at Adafruit made me think to post it: quickref.pdf

By mojo | Posted in avr, electronics | Comments (0)

Hori Famicom trackball protocol

22/04/2010 – 23:34

I just finished adding support for Famicom/NES trackballs to the Retro Adapter firmware. I can now use it as a mouse :-)

The protocol is quite simple. Data is read from the controller in the same way as a normal gamepad. The first 8 bits are the same, followed by 4 bits of y axis offset and 4 bits of x axis offset. Finally there is an ID nibble of 1000. The axis data is in two’s complement format, most likely just the output from some up/down counters.

I opened the trackball up for a look and it uses a custom Hori controller IC labelled “TRK-81-R01″ and “BU3219 844 315″. The only other components are two optical encoders for the ball, two switches (high/low speed, left/right handed), a few resistors, a single power supply capacitor and a 4093 Schmitt trigger. The two ICs are both DIP format. The PCB is single sided and does not use any jumper wires; however there is a patch wire which corrects a off-by-one-pin wiring error. The whole thing could be done in pure logic ICs but Hori must have thought it was cheaper to use a custom IC. Considering the age and limited popularity of the device that’s somewhat surprising.

Unfortunately the deletionists destroyed the Wikipedia article on Hori.

By mojo | Posted in electronics, hardware | Comments (0)

Famicom controller port pinout

19/04/2010 – 00:02

I am in the process of adding support for various Famicom controllers in the Retro Adapter firmware. I have a trackball and a mahjong controller I am working on. I thought it would be easy enough to find the Famicom controller port pinout online, but both of the pages I found (here and here) are wrong.

The correct pinout is:

 1 - GND
12 - Latch
13 - Data
14 - Clock
15 - 5V

There are some other lines connected to the microphone input, but I didn’t trace them. The controller I have has two PCBs held together with wire links so I could not see the markings on any of the ICs or even where many of the traces went. The controller has autofire which works well, although the two speed settings both seem quite fast. My guess is that they are clocked by the latch line so speed would depend on how fast the game reads the controllers.

By mojo | Posted in electronics, hardware | Comments (0)

Playstation 2 controller I/O error

12/04/2010 – 18:49

I have been tracking down the last few bug with the Saturn/SNES to Playstation converters. It turns out that some revisions of the PS2 and one PS2 to XBOX 360 converter both have messed up timing.

The acknowledge pulses come after the next data byte has started. Official controllers can cope with that, but some third party ones don’t work. I’m fairly sure it’s an error as Sony fixed it after a couple of minor revisions. I suppose the probably noticed that some third party controllers didn’t work on one port of the console.

By mojo | Posted in electronics, microcontrollers | Comments (0)

USB devices in VirtualBox

31/03/2010 – 23:15

Getting USB devices to connect to the guest OS in VirtualBox can be a bit tricky. I run it on Windows so it might work differently on Linux, but anyway…

The key is to understand that in order for the device to be detected it has to be connected while the guest OS is running. If it is connected before it is started then it won’t attach. It will say it is, but it won’t be seen by the guest OS.

This small but vital fact is not made clear in the documentation.

By mojo | Posted in software, windows | Comments (0)

HTC Hero, Android and apps review

25/03/2010 – 17:09

I have spent some time with my HTC Hero and thought it was rtime for a review.

I am on contract with T-Mobile and have unlimited data. You really need a good data plan, even if you have WiFi at home and work. Android loves data. Unfortunately T-Mobile’s coverage is crap.

First the phone itself. The design is generally good, and the “chin” makes a lot of sense when you use it. Build quality is good. The only issues I have are that the the volume buttons are too easy to press when using or fishing the phone out of your pocket, and the ringing volume is not loud enough. The latter would be okay if the vibration was powerful enough, but it isn’t. I sometimes don’t notice it.

Sound quality on calls is good, including the speaker phone. The headphone output is rubbish though. Sound quality is below par and there is constant hiss. It makes listening to audio books at low volume a bit annoying. My old N97 was much better. Still, it is usable and at lest there is a standard socket instead of the stupid Nokia pop-port.

Speaking of standard ports the Hero has mini USB. Even better it mounts the SD card as a standard flash drive. No stupid sync software or special modes required. There is a sync app which is on the SD card and is portable (does not need installing). I have not tried it because it does not work on XP x64.

Battery life is pretty good. I normally charge the phone in the evening and then keep it on overnight. I then have the WiFi on all day at work and when I get home the battery shows almost no drain. Of course these meters are often highly misleading but I have been really pushing it lately and it doesn’t suddenly drop right down like my old ipod does. Even with WiFi a.d GPS on for wardriving it comes well. It is easy to charge over usb.

WiFi deserves a paragraph or two. It generally works pretty well, although roaming could be a boy more aggressive. It seems to struggle with very low signal access points. Seems on a par with other phones though.

The most frustrating thing is that it is such a missed opportunity. Android is based on Linux and so in theory a port of aircrack is possible, but lack of driver support is holding it back. Even if there was just a packet capture app… A slightly better antenna would make a big difference too.

The version of Android on the phone has the HTC Sense skin on it. It isn’t that different from normal Android, the main differences being the home screen and they virtual keyboard. The home screen works well. You can customize five pages of. Mixed apps, widgets and shortcuts. I mostly use Android or downloaded ones rather than the HTC widgets as they are q bit big and flashy.

The keyboard is generally good. Vibration feedback is provided buttons make it less responsive. Prediction seems to be excellent and does not overly favour user dictionary words like my Nokia did. After I sent some DNS settings by text it always put ‘DNS’ instead of ‘for’.

The HTC keyboard is a bit different to the standard Android one. I have not really used the standard one so can’t compare, but I hear the HTC is usually judged favorably against it. It lags a bit with the vibration or sound feedback on which sometimes causes it to think you long-pressed a key when you only tapped it. There is no pound key either – a major omission!

I can type pretty fast one or two handed with it. I wondered about getting a hardware keyboard but I don’t think it would be worth it.

Now, the apps. There are so many fantastic apps, and most are free. You are not limited to the app store either, you can install them from any site or the SD card. Apple recently deleted all the WiFi finding apps from their app store and reject a lot of good stuff like emulators and replacements for the built in ones. None of that nonsense here.

One of the best features is the detailed permission display when installing an app. It tells you exactly what the app is allowed to do. The comments system on the store is also very good, and bad reviews are not censored.

The Google apps are pretty good. You obviously need to have a Google account but you can use POP or IMAP etc. with other providers.

The apps all tie together well. For example your contacts brings together gmail, Facebook, Twitter and more. If you install a file manager it can be used to choose files in other apps. All apps can use the notification system.

I only wish the was a WiFi packet capture app, or even better a port of aircrack.

One of the most useful apps is RMaps. It is similar to The built in Google Maps app but can use offline map data. I downloaded all of they greater Tokyo and surrounding areas so that I can have maps when I don’t have am unlimited data connection. The GPS works pretty well once a fix is acquired but it does help to be stationary at first.

By mojo | Posted in hardware | Comments (0)

New Have Your Say forum is rubbish

07/03/2010 – 11:24

The BBC changed HYS. It is just a blog now with moderated comments.

On the one hand it’s good that the BNP can’t use it for propaganda so easily, but the lack of structure means you have no chance of being read unless you post in the first minute of the debate.

The BBC seems to hold the opinions of the general public in high regard. Unfortunately most people are ignorant but still want their say, so some ranking is required. Otherwise you might as well talk to a brick wall for all the good it will do since no matter how insightful and considered your words are no-one will read them.

It also results in a lot id reparation. If people replied to each other the debate might move forwards. Wait, what am I saying? This isn’t a debate.

By mojo | Posted in Internet | Comments (0)

MS Browser Ballot fails

24/02/2010 – 15:06

Just got the first XP machine with the Browser Ballot update on it.

I clicked “next” and IE8 came up with a window asking me to choose my settings. I closed it and selected Firefox from the available options. Internet Explorer opened and downloaded Firefox. I installed it and the browser ballot window was still there. I closed the ballot window and rebooted.

The ballot came up again, but this time even worse:

This thing is horribly broken. Even when you have installed another browser it tries to force you back to IE. It didn’t delete the IE icon off the desktop or Quick Launch either.

By mojo | Posted in Internet, idiots, software | Comments (0)

たとえ溺れても梦はゆめでしかない