logo_PLG

Electronics

ProtoPic2840 Development Board

pic ready onboard 250Looking for relatively affordable one-shot scalability, and being rather limited by the characteristics of the Pic16F84A, I first started by looking at what already existed, just to get a better idea of ​​the problem. I have seen simple and accessible turntables like the PIC READY BOARD marketed by mikroElektronika, and around which it is perfectly possible to "graft" different complementary modules, HP488 317x223or a more complete board like the HP488-00-3 from Matrix Multimedia, E-Blocks compatible, already having a nice user interface ...

or the EasyPIC7 from mikroElektronika, extremely complete ( too much perhaps? ) ... for example ... there are many others ...

My choice is not listed here, yet I would have liked to have fun!
The map I needed, I designed it myself. It has the dimensions of the "Europe" format ( 100x160mm ), and can accommodate all 8-bit Microchip families in 28/40 pins, and I have counted some 127! enough to start playing well ... I voluntarily abandoned the 18 pins support because it already exists on PICÉE. No need to place it again! Apart from these 2 supports 28/40 pins, I doubled that of 40 thanks to tulip bars of 20 pins, allowing to consider a future evolution. The 5 ports each supply a battery of LEDs of a different color ( red for the MSBs, yellow for the LSBs
board easypic7 2
), and communicate with the outside world thanks to male HE10 connectors (2x5), making it possible to connect, for example, modules ( very numerous ... ) compatible with the EasyPIC7 card. I have indeed respected the pinout of their connections. The LEDs of each port can be isolated at any time using coding jumpers, 5 in number.DSCN4596 297x300In addition, total isolation of port A is possible using a dip-switch, which is essential in particular when working in analog mode on these channels. The impedance generated by the LEDs and their polarization resistors would distort the measurements. The board obviously receives a reset pushbutton, as well as a quartz support and an adjustable potentiometer allowing the frequency of the RC oscillator to be adjusted ( 11Hz to 1KHz  values ​​read on the oscilloscope ). The whole being configurable thanks to coding jumpers. Add to this a Led ( green ) to visualize the presence of + 5V,and another ( red ) showing the programming mode via the MCLR line ( ICSP mode).
One small thing that is important ... this card does not have an on-board power supply and for good reason ... it is intended to be plugged into a 32-pin DIN41612 connector in that of the PICÉE development card for which I 've already written a small article. It is a choice which is personal to me, of course, the reasons being the economy of components, and of space on the proto card. And since moreover I do not use the 16F84A at the same time as the 16F877A, why double circuits which can be used again? this is also scalability. On the other hand, I modified it a little because, originally, its LCD display was driven in 8-bit ( on port B so ... ), and the RS and E command lines were taken from port A.easyproto2So I made a small modification on the PICÉE card, consisting in bringing the command lines back to port B, the data now circulating on 4-bit. And here I am for nothing with an E-Blocks compatible card ! DSCN4593 194x150The assembly is powered by a 12V / 1.2A PSS1212 switching power supply unit, and the DB9 socket connected to my PC through a PCMCIA / RS232 interfaceallows the processor ICSP ( In-Circuit Serial Programming ) programming .
However, if you wanted to do it without already having PICÉE, this is possible because, since it is communicating, this card can of course receive an RS232 extension on its C port, and after having programmed a bootloader in your PIC, you will not miss it anymore. a + 5V power supply to make it work. You can see that its field of use is quite wide.
The flexible cable that you can see is a handy little accessory that allows you to connect a port to a development board without soldering ( breadboard ), to which I wired a DS1821 temperature sensor from DALLAS. A little wonder!

The only semiconductor present is the micro-controller ( PIC16F877A ), nothing to panic about, so ...

DSCN4597 232x300
modification of the E-Blocks compatible card ... DSCN4591 289x300
modification of the card wiring ...

To select the 4-bit mode of the LCD display, nothing could be simpler ... I used breakable strips which judiciously enhance the existing one on the PICÉE board. Consequently, bits D0 ... D4 are no longer used. No need to make it more complicated!
There you have it, now all you have to do is program it ...

linkAccess the diagrams & typons ( Scale 1:00 )


Diagram of the IPEEC development board changed e

PICée modified [640x526px]

Add comment
  • No comments found

Quelques liens vers les sites de mes amis...

Licence Creative Commons

L'ensemble de ce site hormis une notification spécifique est mis
à  disposition selon les termes de la Licence Creative Commons
Attribution - Pas d'Utilisation Commerciale - Partage dans les Mêmes Conditions
3.0 France.
Licence Creative Commons

Les Fabricants de Circuits Imprimés que j'utilise

Mes fournisseurs favoris

Vérifiez la disponibilité de votre nom de domaine :