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paceman Guru Joined: 07/10/2011 Location: AustraliaPosts: 1326
Posted: 06:07pm 05 Mar 2013
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Rob, that's a great write-up I hadn't seen before. Did you post a reference to it before on TBS?
Greg
aargee Senior Member Joined: 21/08/2008 Location: AustraliaPosts: 255
Posted: 09:39pm 05 Mar 2013
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Thanks, and yes, probably around the same dates as the blog. Mid 2011.
- Rob.For crying out loud, all I wanted to do was flash this blasted LED.
MOBI Guru Joined: 02/12/2012 Location: AustraliaPosts: 819
Posted: 11:27pm 05 Mar 2013
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I had previously read the UBW article, but had a re read anyway to refresh my memory. Very informative.
A bit of a plus here - I dismantled my ICSP wiring and plugged a led and 47R resistor into header pin 93 (power led) and pugged in a 8MHz xtal into pins 63 and 64 without 22pf capacitors and switched on and after short delay (1 sec), the led lit up.
Then tried it with the xtal on the bread board - still no caps and with 100mm jumper leads to the carrier board, switched on again and same result. It seems it is a bit more rugged than documentation suggests. Have now fitted the 22pf caps.
The PIC32 gets mildly warm but about what I'd expect. About the same as the CGMM.
The Vcap 10uF capacitor is a tantalum SMD (SMT?)and is soldered onto header pin 85 with a 25mm "little blue wire". I'm trying to stretch the limits as much as I can to see just how "forgiving" it is. So far I'm pleased with the result.
Next step is to breadboard the USB socket and see if I can upgrade the MMbasic firmware. Then I'll tackle the SD.
Under side shows wire wrap kynar "little blue wires" as Downwind calls them. They work just fine for me, 1mm strip and solder.
David M.
MOBI Guru Joined: 02/12/2012 Location: AustraliaPosts: 819
Posted: 02:19am 06 Mar 2013
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Update,
I wired up the mini usb to vero board 4 pin male header with "little blue wires". Fiddly job but plugged it in and and ran tera term - It all works. I can write programmes to the carrier board and all works fine.
It also saves files to the A drive - so things are looking positive.
Still have to see if I can get it to download the latest version of MMBasic. Then I try the SD card.
Bed time.David M.
MOBI Guru Joined: 02/12/2012 Location: AustraliaPosts: 819
Posted: 12:25pm 06 Mar 2013
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Well, it downloads the latest version of MMbasic and runs quite happily.
From all my reading into construction and the PIC32 datasheet, it seemed that the PIC32 was rather fiddly getting going but I'm finding the opposite (trust me to)it seems to be quite forgiving. e.g. my 8MHz rock is on a bread board at the end of 2 x 100mm flying leads and with or without the 22pf caps, it worked ok.
The Vcap capacitor that seems to be the source of aggro and system "no works" is only a smd tantalum.
The power supply is a standard 12vdc (transformer and rectifier) plug pack hooked up to a LM317 vreg with a loaded output of 3.25vdc.
Maybe I just got lucky - we'll see when I make another home etched board with the power wiring and decoupling fited.
David M.
MOBI Guru Joined: 02/12/2012 Location: AustraliaPosts: 819
Posted: 02:01pm 17 May 2013
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I had a couple of scrap bits of PCB so I decided to etch some pads for USB, SD card, video out etc and wire to the breakout board. The add on boards are "stapled" to the breakout using some heavy copper wire. It isn't pretty, but it works.
The plan is to make a single sided board with built in 100 pin breakout and with power wiring to suit the pic32.
Why? No particular reason - just something to do while I can still sort of see.
ICSP can be done via headers as can many other occasionally used functions.
This is the direction this product should be heading. Now, if Geoff only recognised the full potential of non-restrictive MMBasic. User defined variables for full relevant PIC-32 I/O pin access.
Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9063
Posted: 10:45pm 17 May 2013
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You think that MMBASIC is restrictive?Smoke makes things work. When the smoke gets out, it stops!
panky Guru Joined: 02/10/2012 Location: AustraliaPosts: 1094
Posted: 01:41am 18 May 2013
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TZ,
Any word on the availability of the previuosly discussed minimal MM systems you are working on?
Regards, Doug.... almost all of the Maximites, the MicromMites, the MM Extremes, the ArmMites, the PicoMite and loving it!
MOBI Guru Joined: 02/12/2012 Location: AustraliaPosts: 819
Posted: 01:58am 18 May 2013
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A minimal maximite is one thing, but having all 100 pins available means that firmware that which is MM based i.e uses the same i/o and structure can be loaded for more specific purposes.
Anyway, I think there is still some of us in Fraggle Rock that are of the "constructor" genre and get a kick out of putting something together with wires and "real" components and getting it working. Sure, tailor made is cheap and easy, but somehow, I don't get a lot of satisfaction in just flicking a switch!David M.
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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