comp-e.com » coding

Pythons in the ‘C’ircus

COMP-E — Thu, 06 Aug 2009 06:39:59 +0000

Spiffy code that is. Stubby has made a few contributions as of late, so check them out. I will be ragging on him to put his battleship game up, but alas it seems it’s lacking comments so we’ll see how long that takes.

I on the other hand, appologize for not tossing up any new coding examples. As of late I’ve been rather busy but fear not for I’ve been dabbling in Python and have some fun stuff to share. To give a bit of a hint, I’ve been playing with the Numpy module and have found it incredibly useful as it ties in exceptionally well with Matlab. I also plan on making a mini program to poll USB for those of you who rely on antiquated RS232 and are left without an easy means of switching over : )

Lastly, I encourage more of you to join and contribute well documented examples to the site. As always, there are no ads and questions will be answered without the arrogant charm of other such code collaborative sites

Creating Morse Code Using The HCS08 Microcontroller

COMP-E — Sun, 22 Mar 2009 15:21:51 +0000

Recently I was faced with the task of sending data out of a HCS08 microcontroller wirelessly. I had only one pin available to me and decided to effectively create Morse Code so that my receiver could decode the signal without having some sort of reference clock to distinguish the 1′s and 0′s. What took many hours to conceptualize and diagram out on the blackboard, turned out to be a very small bit of code.

On the sender side is a simple function written in C that takes a byte and loops through masking each bit. This masking is done inside an if / else block and the result determines whether or not you are getting a dit or a dash.

Tied to the RF receiver is another MC9S08QG8 which takes in the signal via interrupts and assembles eight interrupts into eight bytes. It then does a series of bitwise operations on each of the eight bytes in order to reconstruct the original byte. You will find that a few parts of the code are subject to change (the time for 0′s and 1′s can be adjusted and must be adjusted if you plan on implementing PLL or have a different desired data rate). That byte is then sent to a PC vie RS232 serial port and stored using a free program called RS232 Data Logger from Eltima Software. The code will be posted shortly under the microcontroller section on the COMP-E forum for you to use and enjoy.

- COMP-E

~ ALERT: This post does not return to main !!!

Javascript Examples

COMP-E — Sun, 15 Mar 2009 18:48:00 +0000

In addition to fixing the forum today, I also decided to post a couple ‘fun’ javascript applications that I’ve made. I’m not the best with java script and these two apps are my first attempts. However, they are functional and kind of cool. One is magnetic poetry and the other is a javascript scientific calculator of sorts. I’m not sure how much more I’ll post for javascript examples, but I encourage you to add your apps or examples to the forum : )

- COMP-E

Calculate Min Max and Average Using Assembly

COMP-E — Thu, 12 Mar 2009 22:41:41 +0000

This assembly program reads in 8, 8-bit numbers and is able to calculate the min, max, and average of those numbers. The code has been optimized for speed, but if compact code is what you want, by all means use a looping structure. I should mention that this program is an introduction to assembly and runs on the 8085 simulator. I will however, be posting Verilog code that effectively creates the Intel 8085 and which, will also accept a precompiled hex file via RS232! That will be in a couple months however (time permitting). For now, enjoy your nice and easy Assembly example.

COMP-E

~ we do it with NAND gates

Digital Design with Pipeline 6 Bit Registers

COMP-E — Thu, 12 Mar 2009 22:33:55 +0000

This SLSL / ‘sudo verilog’ program implements the digital design of a pipeline having multiple registers, an adder, and multiplication architecture. The program can easily be re-implemented in Verilog at your discretion. SLSL is a wonderful language that allows for rapid development of digital designs, which is why many of my programs are done in it. Conceptually, you can code from a block diagram to an HDL with it. Unfortunately SLSL is not available to the public, but it should be quite easy for anyone with a couple Verilog or VHDL programs under their belt to understand. The code can be found here.

COMP-E
~a place where computer engineers can play

Nexys 2 Spartan 3 FPGA Arrives

COMP-E — Sat, 07 Mar 2009 19:40:22 +0000

It took a week to get it from Washington state, but it’s finally here. My gorgeous Nexys 2 board I ordered from Digilent. It uses the Xilinx Spartan 3-e chip and has a lot of nice extra features that the one that Xilinx makes didn’t have. Digilent’s website also has a ton of cool addons for the board which I hope to get when there’s some money to spare. I’m going to start out slow and try and reacquaint myself a bit with verilog. My intent is to make a simple calculator and then perhaps move to converting my SLSL code for the 8085 over to verilog. The Nexys 2 board does come with some cool peripherals such as a ps2 port so I may get sidetracked and see what I can do if I hook up an old ball mouse too it. I’ll try to keep you all posted here so the RSS grabs it, but check the forum for code postings and photos. I’ll try to include links as things crop up.

- COMP-E

Digital Design Implementing 8085

COMP-E — Sat, 07 Mar 2009 19:30:37 +0000

All op codes are not represented / implemented in this design however adding them should be very straight forward. This digital design utilizes a bus in order to achieve high efficiency and throughput. The design is scaled back a bit and uses less registers than the actual 8085. This can be easily modified though. Additional op-codes can also be added. Included in this post is are the .src (source) .fmt (format/debug) files. Note that the ‘cpu’ is reading op codes from memory not a .in file!

Click here for the full post including SLSL code.

- COMP-E

COMP-E Forum

COMP-E — Mon, 16 Feb 2009 23:05:00 +0000

Hey all,

The COMP-E forum is starting to grow as I add and encourage others to add usefull new content. Here is a list and quick link guide to all the current topics on the forum.

Signals & Systems

Digital Design Implementing 8085 in SLSL / Verilog

Digital Design with Pipeline 6 Bit Registers (Add & Mult)

Digital Design with Handshakes and the Use of an Arbiter

C – Example Using Realloc And Pointers

Fun With Pointers == Obfuscated Code

UNIX / LINUX / SOLARIS : Implementing the cat Command in C

C++ Linked List : Hash Table : Template Class

C++ Linked List Utilizing A Hash Table – Includes Makefile

C++ Example :: Find Prime Numbers

OS: C++ Using UNIX Commands fork() execv() execev() pipe()

OS: Crack a UNIX Password Using A Dictionary Attack

Operating Systems: Simulate / Create ‘ thrashing ‘

Operating Systems: Create the UNIX ls Command In C++

Assembly 8085 :: Read In Numbers and Create a Histogram

Assembly 8085 :: Read In Characters and CAPS Letters

Calculate MIN MAX and AVG of 8 Numbers Using Assembly

Building a 2-1 MUX and 4-1 MUX Using NAND Gates

An Introduction To IRC

Tweaking and Cleaning Windows + Some Antivirus Tools

All in all, please add to and enjoy the thuroughness of these posts. Remember… if you are stuck on mars and all you have are nand gates, you’ll be all set, for you can build anything with nand gates

- COMP-E

C++ Examples

COMP-E — Sun, 01 Feb 2009 22:05:00 +0000

I’ve added quite a few more examples to the section on C++

( linked lists, hash tables, template classes, Makefile)

follow the link: COMP-E Forum: C++ Examples

– comp-e