The MiniMig PIC update issue thread

[Darrin]

Have you tried screaming "UPDATE YOU USELESS *#&!ING PIECE OF %&$@!" at it?

[odin22]

Again, thanks for the massive rally to help out. You guys are fantastic. You really are. Rarily have I come across a forum as kind and open to newcomers as this.

To all of you who asked about my whereabouts in order to help: Thanks a bunch - I really appreciate the offers and will gladly pay for your trouble. I live in Denmark, and since Andeda has a programmer kit handy and lives "right around the corner" I'm inclined to seize that opportunity if the offer stands.

So how about it, Andeda? Would it be OK if I shipped it up to you? If it's not too much trouble, I'd actually like to send the board along with the PIC just to see if you are able to update it directly before taking the PIC programmer route. Then at least I will know whether my board is truly faulty or not (which would be good to know if I decide to send it back to ACube to fix within warranty afterwards).

[yaqube]

odin22 wrote:

To verify this please remove the PIC from its socket, connect pin 17 and 18, power on the board without the PIC, run terminal program and check if you get remote echo of typed characters.

Ok, I might need some more info here. Do I connect the socket holes on the board where pin 17 and 18 were supposed to go? And with what - a paperclip or piece of wire? Won't that short circuit it?

Yes, you should connect socket holes for pin 17 and 18 together. I hope you know the order how the pin are numbered. Connect them with thin wire with removed insulation at both ends, it would be great if you could cover the ends with tin (I guess you have said you can solder). Avoid paper clip since it will destroy the socket.

That way you will be able to verify if the components on the Minimig board responsible for bi-directional serial communication are not broken.

[odin22]

Darrin wrote:
Have you tried screaming "UPDATE YOU USELESS *#&!ING PIECE OF %&$@!" at it?

I did, actually. Remember the chanting and incantations I mentioned? It was right after that. I even threatened it at gunpoint. A soldering gun, but a gun no less. It was loaded, and I had enough flux to circuit-bend it to hell and back.

[Darrin]

odin22 wrote:
Again, thanks for the massive rally to help out. You guys are fantastic. You really are. Rarily have I come across a forum as kind and open to newcomers as this.

This place is the best when it comes to asking for help, plus many of the developers hang out here too.

[Andeda]

@odin22

Its ok, i just sent you a PM.

[MiniMorph]

Hi there,

I guess this issue is resloved now.

For reference however you can get a very cheap PIC programmer and debugger from microchip now :-

Search for PG164120 on the microchip website.

I know you can get them in the UK for £17 and in the US for
$35.

http://www.microchipdirect.com/productsearch.aspx?Keywords=pg164120

I would not suggest you buying one just to update a PIC on the MiniMig but the option is there and it will allow development and programming on PIC Micros too!

[odin22]

Hi MiniMorph.

The programmer as well as it's low price are certainly intriguing, but it seems to me that this is only half the solution. Since it has no socket on the actual programmer for connecting a PIC, I assume you need an interface board with a compatible pinout for the programmer to communicate with it. Correct?

So where would I find that if I was to look into that solution for future updates?

[Darrin]

odin22 wrote:
Hi MiniMorph.

The programmer as well as it's low price is certainly intriguing, but it seems to me that this is only half the solution. Since it has no socket on the actual programmer for connecting a PIC, I assume you need an interface board with a compatible pinout for the programmer to communicate with it. Correct?

So where would I find that if I was to look into that solution for future updates?

For future updates, I'm hoping that Yaqube's PIC expansion board works out and that somebody puts it into production.  Then you can update your Minimig via a USB memory stick.

[Anding]

Thanks a lot for that tidbit. Checking the ports in my settings revealed the COM ports were set to 9600 baud. However, after setting them to 115200 I get the exact same results. Both on my workstation and the missus' PC.

Do you need to push the baud rate up so high?  I have a little experience with building embedded hardware and find there is always a trade off between coms speed and reliability, especially if a poor connection somewhere is exacerbating the problem.

Would you try and set both sides to 9600 and give it another go?

[odin22]

Hi Anding.

Already tried that. I tried with 9600, 19200, and 57600 baud. No change in outcome.

[yaqube]

Windows settings of serial port baud rate does not matter, Tiny Bootloader app overrides these settings. Besides Tiny Bootloader programmed into the PIC works only with 115200 bps using 20 MHz crystal oscillator. Some (the cheapest) USB to RS232 converters are not reliable when working with 115200 bps speed.

Can you see in Hyper Terminal (set rate to 115200, 8N1, no flow control) any messages sent by Minimig after powering it up?

[odin22]

Hey Yaqube.

The serial ports I'm using on all the PCs are onboard ones. No USB adapters.

I just tried Hyper Terminal with the mentioned settings, powered up the board, and got this:

"Ç▪"

I powered up and tried the PGM reset button a few times more, but it keeps returning the same value. I'm not sure what to make of it.

[Darrin]

odin22 wrote:
I just tried Hyper Terminal with the mentioned settings, powered up the board, and got this:

"Ç▪"

I powered up and tried the PGM reset button a few times more, but it keeps returning the same value. I'm not sure what to make of it.

It an updated Commodore logo!  ;-)

[yaqube]

You should see the following message:

Minimig Controller
by Dennis van Weeren

Try to change the serial port speed in Hyper Terminal to 57600 or lower, it seems that your PIC is operating with different baud rate (although you should see more strange characters than only these two - while Minimig is booting up it sends a lot of characters on its serial port, had you put an SD-Card with minimig1.bin file?). Please also check what is written on the crystal oscillator next to the PIC socket. Is it 20 MHz?

[yaqube]

I have made a small experiment: set my serial port speed to 460800 and I get the "Ç" character as the first after reset. It means that the Minimig transmits 4 times slower than it should.

Maybe you have 4.43MHz crystal oscillator connected to the PIC or the 20MHz one is an overtone oscillator and in your Minimig it oscillate at its fundamantal frequency.

The PIC has programmable bits for oscillator configuration, if they are not programmed to HS mode the oscillator may not be able to operate at its rated frequency. These bits can only be programmed in external programmer.