We've done so many about faces that we're back where we started. Finally.
Our design doesn't fit on the development board we are using, even after we break it into two parts and try to put the parts on the two chips available on the board. Then we decide to switch to a different board, not that we had any other options, and made up the necessary file of pinouts for that board. (The synthesis tools use the pinout information to link the actual wires on the board with the signals that we describe in the hardware definition language.) Once that's done, we work on revising the logic to work with the quirks of the new board. Then when Dr. Smith is helping us with some "bad synchronous description" errors, he mentions that he's got a better board and why don't we use that instead?
His board really is better. So it's back to making another pinout file, because the pins are totally different. We find, however, that this board is so much better that its documentation is ten times as long as the documentation for the other boards we tried. Likewise the chip on the board has got documentation that's two hundred times longer than the documentation for the other chips. Because printing out three hundred pages of stuff will annihilate our print allowances for the semester, we have to root around in these massive pdfs to find the information we need, which is oddly sprinkled through these many, many pages instead of collected in a handy table, as it is for the inferior chips.
So call me Grouchy.
We then spend the rest of the day troubleshooting weird errors that turned out to result from how all the components that were active low (need a '0' to turn on) on the other boards are active high (need a '1') on the new board. Except for the ones that weren't. Of course, if we had reviewed the umpteen pages of documentation, we would have found this out beforehand.
Now that that's all resolved (for the moment), we can start trying to figure out why it doesn't work.
358 words | February 24, 2005 10:26 PM | Ivory tower