Minimig not showing kickstart - help!

[wolfchild]

I have today jumped the hurdle of programming the PIC on my newly self assembled Minimig. 8-)  

It wasn't easy considering that I was so impatient to get it going that I built the programmer myself (RCD prog), only to find that it wouldn't work with the Minimig's PIC.  I finally hacked and it let me program the darned PIC.

Now I have yet another problem.  Upon power up, the Minimig seems to pass the RAM test (screen flashes green, red then blue) and then it starts loading kickstart (different colour screens with 'decrunching' flicker every now and then).  It then stops at showing a blue screen, and that's it.

The OSD works, and I can insert floppies, but nothing else happens.  I did not even get the kickstart screen.  

I was using a 32MB Panasonic SD card and KS2.04.  I'll try tomorrow same card with KS1.3.  I'll also give it a try with a 2GB SanDisk and KS1.3.

Has anyone been through this problem? Any hints about what's happening? I'm using the latest release from Dennis and no PIC bootloader.

Cheers!
Edwin

[Namek]

I have the same problem first time I try my minimig, the problem was the SD, copy the files to a different SD and try again. Good luck.

[wolfchild]

@Namek - Thanks for the tip.

I just tried the 2GB SanDisk.  Still the same problem. :-?

Last activity that happens is that the NumLock LED on the keyboard turns off.

I'll give the sources a look to see what might be happening.

[BraindeaD]

Hi Wolfchild.

When I tried to program the PIC without bootloader with the last Dennis' release, the PC client gave me error because some config words (I'm using PICKit 2).
Try to program the PIC with the bootloader, and update it with the last Dennis' firmware (or another one) via serial. It works for me flawlessly.
Hope this helps.

Regards

[wolfchild]

Hi,

I encountered that problem too.  The firmware from Dennis does not set the config words, so I set them manually by copying those from the bootloader.

Which hex file did you use for the bootloader?  I went to the author's site and downloaded the latest TinyPic distro (version 1.97).  There is one for PIC18F252 and I programmed that.  It did not work for me however, so after a day's worth of trials, I gave up and flashed the Minimig firmware directly, and put the config word manually.

Currently I am programming using WinPic and a modified RCD programmer.  I should be receiving my PICKit2 clone shortly, but in the meantime I can't wait to get my Minimig up and running!

[BraindeaD]

Hi,
I used the "tinybld_18F252_20MHz.HEX" file as bootloader, included in Tiny PIC Bootliader program by Claudiu Chiculita...
Trying serial update, sometimes the Tiny PIC Bootloader failed searching the PIC because the serial connection weren't correctly attached in the port.

[boing4000]

I sometimes had the same problem after loading the kickstart. In my case it was a problem in kick.rom file, due to some unknown reason the file was damaged and could not work in minimig. After storing the same 512kb kick.rom (kickstart 1.3) file again it works.
Also try to quick reformat the sd card with FAT16 and fist of all store the minimig1.bin and then kick.rom file. After that you can store the adf files (order as saved) in root dirctory.
Maybe the tiny fat16 PIC firmware can not read the two files correct if they are far behind some .adf files or if they are fragmented.
Also try different kickstart version, only neat 68000 kicks will work in minimig. A1200/A4000 rom images expect 020+ cpu and will fail even in real A500/2000 with installed 68000.

In all cases after loading the kickstart into memory the minimig should do a reboot/reset. If that fails it will still show that last screen color. Try to reset manualy with ctrl+alt+alt.

[wolfchild]

@ braindead
Thanks for your info!  You helped me a lot!  I used the bootloader you mentioned and it worked flawlessly.  I had to change serial cable too (must be null modem).

@boing4000
Following your post mentioning the reset, I put a logic probe on the 68k reset pin and in fact it goes LOW just after it completes flashing colours.  This also happens when I press ctrl+alt+alt.  So it seems that the 68k bootcode is working fine, and so is the core.

What I noticed is that the 68k and RAM buses are active during loading of the kickstart, but then go completely idle after the reset.  The only activity remaining is the CPU_CLK signal (68k pin 6).

I'm using a 512k KS1.3 and tried FPGA cores from Dennis and Yaqube.  If I don't get it running by end of week I'm going to shelf it until I have time to write a kickstart replacement that runs some extensive RAM tests.

I suspect there is some broken track somewhere which I can't see...

[BraindeaD]

Great!
I had the same problem a few days ago, and (I think) boing4000 gave me this solution. It works great.

[boing4000]

wolfchild wrote:
What I noticed is that the 68k and RAM buses are active during loading of the kickstart, but then go completely idle after the reset.  The only activity remaining is the CPU_CLK signal (68k pin 6).

I'm using a 512k KS1.3 and tried FPGA cores from Dennis and Yaqube.  If I don't get it running by end of week I'm going to shelf it until I have time to write a kickstart replacement that runs some extensive RAM tests.

Your minimig system seems to work just fine. All system clocks are operating, else the kickstart flashing would not appear because this is done by the bootloader block-rom inside the fpga core and 68000 processing.

I would say that there is (still) something wrong in your kickstart image file. Please check it (again) in UAE or just dump a fresh image right out on an working Amiga.
If this kick.rom file is already working with UAE, I can not really tell whats wrong.

A ram test is already present in the current core from Dennis: red, green and blue screen colors before loading the kickstart into ram. It tests with $55555555 and $AAAAAAAA pattern.

@BraindeaD
Im glad to be at service

[wolfchild]

Thanks for your help guys!

I made another step forward.  I found that an address pin (A14) on one of the RAM chips was not soldered properly. (Shame on me, as I used to make SMD protoypes for a living up to 6 months ago!)

After fixing it, I have now a black screen, and activity on the RAM and CPU buses.  

The kickstart I am using works with UAE, so I still have some more hardware issues to look into.  I suspect a faulty RAM...

Unfortunately, the RAM test as provided by Dennis is not flawless and it will not detect problems on address lines.  Currently, on a faulty system it will write data to a wrong address and read it back from the same wrong address.  Only data line problems will be detected...

I found a better algorithm, from memtest86 tech info and if I do have time, I'll write my first ever 68k asm program which will be an extensive RAM test

I'll keep you guys posted.

Cheers!
Edwin

[boing4000]

I wish good luck in finding the problem. Especially the Spartan fpga is very tricky to solder. I also did a bugfixing on an selfmade minimig from a friend, there was a short circuit between 2 pins from behind (not visible)!
Its hard to find out but I hope you can fix it.
PS: S-RAM is not that easy to damage, just for thinking positive