Tuesday, March 22, 2011

Borked it!

My gosh, I was hoping to be more frequent this year with blog posts, which I have been doing on FaceBook, and a couple of other places, but forgot here as well.

What has been happening?
Well I have built up the RepRap as far as I can, till I can calibrate the electronics, so endstops are still not made yet.
We then had an open day at Tangleball, but I managed to bork my computer up last Thursday, because the RepRap electronics were not communicating on the Tangleball PC's running Linux, so I though, well let's try installing the RepRap software and Linux onto a flash drive.
Whoops I forgot to unplug my other hard drives, so Super Grub managed to not only corrupt the bootloader on the flash drive, but also on the Linux partition and Windows hard drives, and the day of the open day was looming, luckily Jaco was able to give me a hand to get the Linux partition working so I could back up my data before trying to fix the Windows hard drive bootloader.
Then I remembered i had installed Windows 7 Beta, which in turn rewrote the bootloader on the Windows disk as well some time ago, so my thinking was "Oh hell!", and some other profanity! So I went into town on Saturday, after spending time with my mum in A&E at Auckland hospital, went into PB technologies, and thus bought Windows 7 and another hard drive.
Got home some time later, and after dinner sat down with 4 disks, yes 4 disks.
Windows XP home CD
Windows 7 Ultimate DVD
Ubuntu CD
Ultimate Boot CD

I ended only requirring the Ubuntu and XP disks, first XP, with all hard drives disconnected, boot with disk, then at the Recovery Console, I typed "fixmbr", thats it.
Reboot after removing disk, and the message Unable to find bootable disk. Arrrgh!
A few moments later realized that Jaco disable the boot flag on the XP drive, so a quick search on Google, found that all I had to do was boot with the Ubuntu CD, and at the terminal, type "gparted", then click the check box for the hard drive to become bootable.
Take out the disk and reboot.

Yay, what a relief to still have all my data back.

Now I had no time to even try doing what I was going to do, so I resorted to taking my WHOLE computer to the open day, an run the RepRap from that, cause I know it worked fine after fixing my computer.

Had a good crowd around me early Sunday afternoon, until Vik came, then after about an hour, even my computer stopped communicating, and I tried many ideas to get it working again, but nothing, my only hope was to take the electronics and install everything up at work to use, of all things, an oscilloscope.

On the Tx and Rx lines, the Tx was always high when rebooting the electronics, and there was signal to be expected on the Rx line. How could this be? So I scoped both pins during programming on the same port, and there was signal on both Tx and Rx pins, serial comms works, but doesn't, huh?

This doesn't make sense. In this case, normally at work I would change the CPU, which I did, because I had just one remaining ATMEL 644P processor, bought two to fix a problem last year with not even being able to download the bootloader,, the chip had an internal short, however this time, it seems that just 1 register, used for serial comms was faulty, just 1 freaking register. If it were a Friday I would be raging.
So I replaced the device, flashed the bootloader, then the RepRap firmware.
Next test was to use LynxTerm, a simple terminal program, cause Windows 7, on my work computer, does not have HperTerminal. That is ok, as LynxTerm verified that with a reboot of the electronics, there in black and white is what I have been striving for, the word displayed "Start".

Its not much but it verifies that there is serial comms now. Jst got to update the firmware with the correct version at home, then test it at Tangleball, then i'm off to do calibration again.