Micro-KIM weekend

-
A rainy weekend was a perfect excuse to play with my micro-KIM, which had been collecting dust in a drawer for too long. I had fun using my own cross-assembler to develop and generate programs in paper tape format, and upload these to the micro-KIM via the PuTTY client.

I figured out how to use the 6532 RIOT to set up a timer-based interrupt service, which is an important step in separating actual computation from display and keypad handling. The following clip shows the difference between incrementing a three-byte memory counter at roughly 1000 times per second (timer delayed) and 100,000 times per second (full speed with about 10 cycles per iteration at 1MHz). Perhaps a nice illustration of how fast even those early computers were.


Comments

Post a Comment

Popular posts from this blog

Checkers Move Generation

-
I was able to make a small improvement in the checkers move generator (written in Java for the Android SDK). The following table shows run times of several perft depths before and after optimization when run on the emulator (which should mimic actual run times on the phone quite well). DEPTH #LEAF NODES ORIGINAL OPTIMIZED TIME TIME ==================================== 7 179740 2.9s 1.9s 8 845931 14.2s 9.7s 9 3963680 66.3s 45.6s 10 18391564 294.6s 208.7s P.S. Runtimes for a C++ checkers move generator on a 2.2 GHz Core 2 Duo are given at my checkers page .
Read more

Connecting Chess for Android to a Remote Server

-
Image
I have received several questions on how to connect Chess for Android running on an Android device (e.g. a phone) as client to a remote chess server (e.g. a powerful desktop), so I decided to write a small document with detailed instructions. What you will need: The server software from Bernhard Wallner's chess utilities , suited for your server's operating system (if, say, your desktop runs Windows, you will need to download the Windows version). You do not need to download the client software in this case. The network enabled version of Chess for Android . On the server, start the engine server software, and construct a new row for every engine you want to run remotely. Assign a name, port number, and select the full path to each engine binary (an executable that runs on the server). You can also supply command line options for starting the engine. Check the active checkboxes and click start when done. This yields something similar to the screenshots below. Here, I have s...
Read more

Connecting with the DGT Board

-
Image
After all the fun I had connecting Chess for Android with the Millennium  over Bluetooth, I was curious if I could provide similar support for the DGT electronic chess boards. Some of these have Bluetooth capabilities, most use USB connections, and some older models, like the one I have, still use the RS-232 connector. To my pleasant surprise, by combining the original serial cable of DGT with a USB-to-serial cable and a female-USB-to-USB-C cable, I was able to get an actually working connection between my DGT board and my tablet or phone. Next was implementing support in Chess for Android. Luckily, DGT kindly shared the protocol documentation with me, and after a fun weekend of hacking, Chess for Android now proudly supports DGT electronic chess boards as well.
Read more