Archive for the DSP Laboratory Category

Ah well, back to the drawing board

Posted in DSP, DSP Laboratory on August 28, 2014 by asteriondaedalus

db25flop

So, the most of $2 device turned up.  Promised to be a Parallel port but looks to pass as a parallel printer port.  I am not sure that the eeprom programming software recognizes it at all.  Opted to get a $9 PCI card after all so things on back burner there again.

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How hard is it to program a eeprom?

Posted in cheap obsolete tech, Development, DSP, DSP Laboratory, Hardware on July 29, 2014 by asteriondaedalus

Pretty tricky if it is obsolete so no programmers around for it.

The AT17C65 is the eeprom configurator used in the eval board that the ADMCF328 sits on.

You can probably see where I picked up the fidgety RS232 approach with the AD chip and the optocouplers.

Now I know what you are thinking.  Swap it out for another chip.

Kooky idea.

Except the of the three chips that the ADMCF328 are design to work with (XC17165E, AT17C65, or 37LV65) the AT17C65 is the only one I can readily find on the aftermarket in China.  Absolutely no programmers for it though (although ATMEL have a tease page for a programmer but you can’t get it anymore, and why would you as the chip isn’t stocked anymore).

Thank you Mouser for one idea of how to build a programmer.

Although clincher came from ATMEL site along with the software for the configurator.  So, since the software seems to install on my Windoze box, I just need a DB25 parallel port – yes I said a DB25 parallel port.

Now, this goes either of two ways.  First is a USB to DB25 cable and driver, hopefully the configuration software recognises that arrangement.  Total cost $1.98.

Failing that, $6 to $11 dollars for a PCI card with DB25 parallel port and the ATMEL configurator software.

Failing that, ATMEL has also provided AVR code for programming AT17C65 so I would just code something up on my Arduino MEGA1250.

Okay, so either of 3 ways, 4 if you count no can do – which we don’t do we!

Why all this trouble?

Later chips work slightly differently and there is no guarantee the ADMCF328 will read other chip types.  Since getting a flashing LED on this little DSP chip will be proof I can program it having the right eeprom makes sense to avoid compounding the problem.

Although, the first flashing LED experiment will be against serial port boot.

Stay tuned.

PS, no Maker get out clause no way no how … I like it.

 

Got there

Posted in DSP, DSP Laboratory, Hardware on July 23, 2014 by asteriondaedalus

So, a little birds nesting and a lot of fiddling convinced me from moving away from the AD chip with opto-couplers.  So, I went for a MAX232 after all, with benefits.

db9rs232

Why not?

So the setup for the ADMC32x is now:

More sensible

More sensible

The other side is this module is more useful as I can use it on other experiments.  The other way was too sensitive to bumps and knocks and I need a “quiet” interface because the problem is working out whether I am getting code onto the chip – and not whether my birds nested serial interface is up or not.

10MHz clock is still coming from MAX CPLD.

Getting there

Posted in DSP, DSP Laboratory on June 29, 2014 by asteriondaedalus

Setting up (slowly) for experiments with the ADSP 21xx based ADMCF328 chips I grabbed of internet for cheap.

First step, set up to program them from serial line.

Based on the manual for the ADMCF32X PROCESSOR BOARD we need opto couplers between the RS232 line and the ADMCF328 for some dang blasted reason.

So, rather than go feral, I pieced together the actual chips from the board from the time machine of the internet.

Let's not stray too far from the original - for now

Let’s not stray too far from the original – for now

 

So, I will use my CPLD board to generate a 10MHz clk signal, rather than fiddle with a crystal.  For the moment I am going to go without the NME0505S although the mixing of analogue and digital gnd may be a little fiddly.  Although, this was inherited because I elected to go with the AD7306BR (an hence the opto couplers).   It may have made more sense to go with a MAX232 or similar.

The initial experiments will be LED lighting and driving my LogicSniffer by the PWM pins.

DSP oi, oi, oi, DSP … done that already have I?

Posted in DSP, DSP Laboratory on June 10, 2014 by asteriondaedalus

Author/lecturer has made his text on digital signal processing available online here.

The wild thing, he has a lab book based on the ADSP 2181 EZKIT LITE, aka:

ADSP 2181 EZ-LITE

ADSP 2181 EZ-LITE

I am so rusty after a decade or more so this is perfect.

Also wik, I got a half dozen SOIC28 to DIP28 breakouts and worked out my soldering is out of practice, my $400 prescription glasses are no good for close work, my 10x magnifying lamp distorts my vision, and the pads on the breakouts are tinned so I need only sweat the pins and don’t need to add solder per se – to the SOIC chip at least.  I do also need a new tip for soldering iron and a new roll of de-soldering wick.  All lame excuses for a shoddy soldering job lol.

Why buy a DIP package?

Why buy a DIP package?

I have to set this up for flashing LED to sort out getting code onto the chip.  I may not be able to flash the on board FLASH as the flash utility seems to be the only dang blasted tool to require a licence – all the others run fine.

So I can make prom code and do likely load serially with a little playing so a test run to get the LED flashing on the EZ-LITE board and then wiring something up on the breadboard.

Still looking for a way to cheaply program AT17LV65 or AT17C65 to set up for EEPROM boot – eventually.  I might be able to use an Arduino (my Mega1280 perhaps).