Monthly Archives: July 2010

Implemented CDP1802 “load mode” in VHDL model

Posted on July 25, 2010 by Eric

My 1802 model was missing some state transitions necessary for load mode to work properly.  Load mode occurs when CLEAR and WAIT are asserted simultaneously.  In this mode, DMA operations can occur, but no instructions can execute and no interrupts … Continue reading →

Posted in FPGA, RetroChallenge | 1 Comment

VHDL switch debouncer for FPGA-Elf

Posted on July 24, 2010 by Eric

I think I’ve already written VHDL code to debounce switches, but I can’t find it at the moment, so I’ve just written new debouncing code for the FPGA-Elf.  The system clock is divided down to produce a debounce clock of … Continue reading →

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FPGA-Elf front panel assembly started

Posted on July 24, 2010 by Eric

The aluminum front panels Jim Donnelly machined for me arrived today.  I was originally planning to paint it black then laser-etch the legends, but I don’t think I’ll have time, so for now I’ll leave it bare aluminum.  I think … Continue reading →

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FPGA-Elf front panel parts arrived from Mouser

Posted on July 21, 2010 by Eric

My order from Mouser Electronics, fifteen toggle switches, two pushbutton switches, and two hexadecimal LED displays, arrived today.  UPS ground shipping from Mansfield, Texas to Denver, Colorado took two days. The Elf only needs eleven toggle switches and one pushbutton … Continue reading →

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USB tethering an Android phone to an OpenWRT router

Posted on July 21, 2010 by Eric

Now that I’ve got OpenWRT 10.03 “Backfire” running on my DIR-825, I decided to take advantage of the new USB tethering feature of Android 2.2 “Froyo”.  I connected my Nexus One phone to the USB port of the DIR-825, and … Continue reading →

Posted in Android, OpenWRT | 7 Comments

Installing OpenWRT 10.03 “Backfire” on a DIR-825

Posted on July 21, 2010 by Eric

I did a fresh install of the jffs2 build of Backfire on a D-Link DIR-825.  I could have used the squashfs version, and have done that in the past, but using the jffs2 build makes it easier to use an … Continue reading →

Posted in OpenWRT | 1 Comment

Obtaining 1/8″ aluminum

Posted on July 21, 2010 by Eric

Many people recommended ALRECO in Henderson, Colorado (near Brighton) as a source for aluminum.  I haven’t been there, but I’m sure they would have been able to satisfy my needs.  However, before I found out about them, I discovered that … Continue reading →

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Working on front panel layout for FPGA-Elf

Posted on July 18, 2010 by Eric

I’m laying out the front panel for the FPGA-Elf.  A friend has offered to machine it for me on his CNC mill!  Should look really nice.  That saves me lots of time that I can use to whip the VHDL … Continue reading →

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Ordered parts for FPGA-Elf front panel

Posted on July 17, 2010 by Eric

I just ordered the parts for a front panel for the FPGA Elf.  The original Elf design needed double-throw switches, but the FPGA version only needs single-throw.  I wasn’t able to get toggles with colored handles on short notice.  I’m … Continue reading →

Posted in RetroChallenge | 2 Comments

Installed Xilinx ISE WebPack 12.1 on Fedora 12 x86_64

Posted on July 15, 2010 by Eric

I’ve moved most of my development activities onto my new notebook, running Fedora 12 x86_64 Linux.  Today I installed Xilinx ISE WebPack 12.1 on it.  ISE is officially supported on Red Hat Enterprise Linux, but not on Fedora.  Fedora is … Continue reading →

Posted in FPGA, RetroChallenge | 6 Comments