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ScaleRobotics
- 22nd April 2010, 07:49
Hey guys, those of you that have the EasyPic6 development boards, do they allow voltage adjustment for 3.3 volt parts, like the 18f26j50?

Thanks,

Walter
malc-c
- 22nd April 2010, 08:09
Walter,

Have a look at the EasyPIC6 manual (http://www.mikroe.com/pdf/easypic6/easypic6_manual_v100.pdf) - page11 shows the schematic for the power supply, which appears single rail 5v

From the Mikroelectronica forum http://www.mikroe.com/forum/viewtopic.php?p=121318#p121318
ScaleRobotics
- 23rd April 2010, 08:37
Walter,

Have a look at the EasyPIC6 manual (http://www.mikroe.com/pdf/easypic6/easypic6_manual_v100.pdf) - page11 shows the schematic for the power supply, which appears single rail 5v

From the Mikroelectronica forum http://www.mikroe.com/forum/viewtopic.php?p=121318#p121318

Thanks Malc. All those jumpers, but none for 3.3 volts? I guess I was hopeful. I have an EasyPic6 coming in the mail, but it looks like I will have to breadboard the 3 volt varieties.

Thanks,

Walter
malc-c
- 23rd April 2010, 09:24
It'll probably be a feature of the EasyPIC7 board ;)
jellis00
- 24th April 2010, 02:53
As an EasyPic6 user, I posed the same question to Microelektronica in a ticket to their tech support. It took a couple of interactions, but they do have a solution if you are using the extended ports on the EasyPic6 with one of their ProtoBoard. Here are my exchanges with them in reverse chronological order if you are interested.
------------------------------------------------
You can use EasyPROTO for your application.
http://www.mikroe.com/en/tools/easyproto/

Best regards

Slavisa Zlatanovic
mikroElektronika [Support Department]
--------
As I said in my previous email, the 5V-3.3V translator won't work when using more than one of the port expanders with PROTOboard.

Another approach that might solve my problem would be using flat cables from all 3 ports of the EasyPic6 to the PROTOboard, which would then permit insertion of the 5V-3.3V translator into the circuit for just the single port that I need to convert the voltages for. I see on your web site your product "Flat Cable 1 Extra Development Board", but it has female connectors on both ends. What I would need is a flat cable with female on one end (for connection to the EasyPic6) and male on the other (for connection to the PROTOBoard)....do you have such a product? If so, what is the price?

Regards, JE
-----Original Message----
From: mikroElektronika Support Center [mailto:[email protected]]
Sent: Monday, March 29, 2010 2:05 AM
To: [email protected]
Subject: [SUPPORT #SHW-490341]: How to get MCU logic levels to 3.3 volts for LCD compatibility?

Hi!

We recommend you to use our 5V-3.3V Voltage Translator.
http://www.mikroe.com/en/tools/voltran5/
That way you will not have to worry about different voltage levels.

Best regards
---

Slavisa Zlatanovic
mikroElektronika [Support Department]
rmteo
- 24th April 2010, 03:15
I have used 3.3V PIC's (including 16-bit devices such as the PIC24 in the picture) with an EasyPIC4.

4282
ScaleRobotics
- 24th April 2010, 06:06
Thanks guys. It looks like the MC34063A switching regulator allows down to 3 volts with a change of voltage adjustment resistors R56 and R55. Also looks like most chips on the board might also be 3v tolerant. I'll have to look at it some more. Don't know if the lcd's will work at 3.3v though. Hopefully enough functionality in the rest of the board to get by. What did you find out rmteo? Is this what you did, or are you powering it directly from the pickit2?

Walter
rmteo
- 24th April 2010, 14:09
Both the LCD and GLCD work with 3.3V input signals - the LEDs will be a little dimmer as the PIC sources current to them. As long as the external PIC is powered by its own separate supply (3.3V from the PicKIT2 in my case) and share a common ground, most of the peripherals on the EasyPIC work fine. The EasyPIC is powered by its own on-board 5V supply. I have also tried UART communications between the on-board 5V PIC and the external 3.3V PIC and it works.

Obviously, the external PIC will need to be programmed (and/or debugged) using something like a PicKIT2 (and the appropriate development software). PicFLASH does not support 3.3V only devices. As mentioned previously, this technique allows you to work with other devices such as PIC24/dsPIC33 besides 8-bit PIC's on the EasyPIC. In fact, I have tested this with 32-bit MCU's from NXP and ST as well.