Universal PI Micro

[johnno]

upmd

Hi BW I counted 648?
is that what you where showing with the 5 buttons pressed? I hope Im not being picky as I have no Idea of how sensitive
this screen can be,...give or take some small % error.
johnno

[bugwhiskers]

Bar graph & Joystick

The bar graph has been programmed in.
The digital range is 0-1023.

There are 16 characters * 5 vertical lines giving a range of only 80.
To give maximum sensitivity to the bar graph it has to have an offset from zero ie adjustable so the left most bar is just visible at the point of threshold.

The Joystick (or 5 buttons) are now being read, the following table shows the number generated by each button.

No button=255
CP(center press)=210
North=169
East=126
West=90
South=53

There is approximately 40 between each reading so noise won't give a false reading.

regards
bugwhiskers

[bugwhiskers]

Display

The 16 character * 2 line backlit display is up and running. The UPIM daugher board can be seen in the middle of the large PCB.
I have decided to enlarge the daughter board and incorporate the other SMD device, the "G" sensor on it.

The numbers are leading zero blanked, ie you don't get 002 for the number 2.

regards
bugwhiskers

[bugwhiskers]

Looks like your are about a year ahead of what I am working on using a Stamp module. From the looks of it, it will be a pretty sophisticated controller for a detector. Thanks for sharing.
RayNM

Hi Ray-NM,

Thanks for your interest in the project. It is essentially an engine to drive a lot of "standard" PI's. By standard I mean 2 JFET's or Analogue switches to toggle, an IRF740 MOSFET, requirement for a battery voltage doubling circuit to supply the +V of the OP Amps etc and the all important audio. It also has a screen which will allow those without the luxury of a CRO to see just what timings (in microseconds) their circuits are operating under.

Later I will make a set of drawings that will show where the UPIM is plumbed into the likes of the Hammerhead, Gary's PI and GoldscanIV.


regards

bugwhiskers

[bugwhiskers]

UPIM update

The attached .pdf's show the revised schematic(the fat has been trimmed), and the PCB layout. The board is single sided with only a handful of jumpers (the small square pads) required.

The little orphan chip is the "G" sensor that still has to be plummed in via an adaptor board like the micro.

Resistor and cap values will be added after the prototype is running smoothly.

The PCB measures 3" * 3" square.
regards

bugwhiskers

[Ray-NM]

Way ahead of me

Looks like your are about a year ahead of what I am working on using a Stamp module. From the looks of it, it will be a pretty sophisticated controller for a detector. Thanks for sharing.
RayNM

[bugwhiskers]

Revised UPIM overview

The attached .pdf shows changes to the schematic. Support for a backlit LCD has been added. Support for a 3 axis "G" sensor and either a Joystick or 5 push buttons has been added also.

There is one spare I/O pin, any suggestions for it's function.


regards

bugwhiskers

[bugwhiskers]

SDM adaptor board

The attached pic shows the bottom side of the SMD adaptor board. Bypass caps, headers and XTAL components in place.

Work on the main board schematic is about half done. Very slow because I have to make the schematic symbols and packages as well because a lot of the parts aren't in the libraries.

regards

bugwhiskers

[bugwhiskers]

SMD to thru hole

The attached pic shows the first prototype board ready for drilling and soldering.
The board now includes provision for an external XTAL to enable running the micro at it's full speed 20 MHz.

regards
bugwhiskers

[bugwhiskers]

Micro SMD to thruhole adaptor board.

Attached .pdf shows a 1" * 1" board to adapt the SMD micro to thru hole. The bypass caps for the micro are on it too. Contemplating putting the external XTAL on it also to cut down on radiated noise.

regards

bugwhiskers

[bugwhiskers]

Joystick input

The attached .pdf shows how a 5 switch joystick type input device would be configured.
Each resistor has a different value(to be determined). When each switch is closed a unique voltage is presented to the AtoD. The software is set up to look for a "range" of a voltage, ie 3.7 to 4.1 then performs a predetermined action for that range. Using this arrangement diagonal movement of joystick and indeed any direction plus centre press will give 19 different voltages.


N=NORTH, E=EAST, S=SOUTH, W=WEST C=CENTRE PRESS

C
N,S,E,W
NE,SE,SW,NW
C+ N,S,E,W
C+ NE,SE,SW,NW

regards

bugwhiskers

[bugwhiskers]

Hi johnno,

The schematic and board are being done with "Eagle" light.
As for the "G" sensor (G for gravity, not Groin) the schematic has been changed to incorporate a 3 axis type. The X,Y axis will be used to detect sweep speed/or lack thereof and the "Z" (up down) axis may be used to instigate ground balance.


Support for LED backlit LCD displays has been added also. The micro chip, which is only about 5mm*5mm with 0.3mm leads only 0.8 mil apart will be mounted on a small circuit board with standard 0.1" pin headers. The rest of the circuit board will be standard 0.1" thru hole components making it much easier to construct, modify and repair.

Another option under consideration is the use of a small joystick as the main input interface to the micro. The joystick would provide 5 inputs, up, down, left and right and pressed. This would make for a very uncluttered control panel.

regards
bugwhiskers

[johnno]

how's it goin' BW

Just a quick note as to how things are progressing?
Also that "G" spot sensor thing...you'll make a million on that alone!..
is that on Protel?
johnno

[johnno]

Thankx BW I will wait till things settle out..
Thanks johnno

[bugwhiskers]

Hi johnno,

A bit early to be able to quote a price. Some people may want to supply their own LCD screen, and others may not want the "G" sensor. Sometime soon I hope to have a price for the board with just the CPU soldered in (it's a SMD).

regards
bugwhiskers