Honored Contributor
Honored ContributorHi Justin,
--- Quote Start --- Thank you for the prompt response. My calibrations are for 9 photo diodes on a specific chip. Each diode reads different light counts out of the factory so I have been calibrating all 9 diodes to initialize around 390k counts in dark and 6 million counts when a uniform, test light strip (basically a night light) is exposed to all 9 simultaneously. By varying multipliers and offsets (y = mx + b since they should all be linear and hopefully very close) in lab view, I then put the corresponding hex values into my VHDL Quartus program. --- Quote End --- How do you put them in your VHDL? Are you creating hard-coded registers that are effectively read-only, or are you putting them into a RAM image? Either way, at power-on you should be able to read these read-only registers and confirm they are the calibrated values. That of course assumes you have created a design where you have some method of reading those registers back - have you? If not, then I recommend using the JTAG-to-Avalon-MM bridge and putting the calibration values in registers that you can read via the JTAG bridge. If what I am saying is complete gibberish to you, then take a look at this tutorial I wrote: http://www.alterawiki.com/wiki/using_the_usb-blaster_as_an_sopc/qsys_avalon-mm_master_tutorial Personally I would create a block of registers that have a build time-stamp, a calibration serial number, and the calibration values, and then have those map to some database of calibration values. Ideally the board would have some unique way to identify it too (1-Wire ID, or perhaps the SPI Flash has some one-time-programmable memory or a unique serial ID). Cheers, Dave
