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Hi guys,

 

Sorry for being ask for help again, but this time isn't a coding help, is about the MCU's themselves.

 

I'm trying to build a RGB led dimmer (like heartbeat) and I need to know two things:

 

1- (most essential) it's possible to "transfer" the MSP430 chip to a breadboard and work without the launchpad board attached? The "secret" behind the name "LaunchPad" is program the MCU and then "Launch" it to a breadboard and use it without connecting it to a PC for power/comunication.

 

2- all the MSP430 MCU's (G2231, G2211, etc) can handle with analogWrite, or just the 20 pins ones?

 

Hopw you can help me once again guys.

 

Thank you very much.

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Thanks spirilis!

 

And where can I found a scheme like this one to see which pins are analog capable?

 

And I don't have to make any special connection with RX and TX pins (P1.1 and P1.2) when transfer the MCU to a breadboard?

I'm not sure if anyone's put together a colorful graphic like that, but all this information and a lot more can be found in the Datasheet for the chip-- see the product page http://www.ti.com/product/msp430g2231 and download the first PDF, "MSP430G2x21, MSP430G2x31 Mixed Signal Microcontroller (Rev. J)" and check out page 3.

 

Hmm actually looking at that datasheet, it looks like the G2231 only has 1 usable analogWrite() output.  That can be P1.2, P1.6 or P2.6 but only 1 of them can be used for that at a time.

 

All the "TA0.x" pins are analogWrite() capable *except* TA0.0 ones, like P1.1, P1.5.

 

Problem is though, I think the Software Serial library uses that P1.2 timer pin for its own work.  So you can't use analogWrite() and Serial at the same time.  I guess you need the 20-pin versions (and preferably the G2553 which has its own hardware serial) for maximum analogWrite() capability.  Probably not going to drive an RGB LED from one of those 14 pin or 20-pin G2xx2 (e.g. G2452) chips since you need 3 PWM outputs.

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And I don't have to make any special connection with RX and TX pins (P1.1 and P1.2) when transfer the MCU to a breadboard?

 

I have put both LaunchPad chips on breadboards, it works fine. Push it in over a breadboard split and go nuts.

 

The key is to pull the RST pin UP, meaning to Vcc (as opposed to grounding it). Grounding RST is what resets the chip, so pulling it up via a pullup resistor (something like 47K ohm should do) brings the chip to life.

 

And hooking up Vcc and GND to the appropriate pins, of course.

 

From there, you can still program the chip, in place, with a Launchpad. Basically, you just use the emulation side of the Launchpad (those jumpers along the dashed line) and connect to Vcc, GND, RST, and TEST. Stick those connections in the breadboard at the right spots, connect the Launchpad to USB, and the chip will be visible to flash as if it were in the Launchpad socket.

 

Good luck!

 

PS: You can get sample chips from Texas Instruments, including the 553 and 452. So, you can get some spares, if you like. Don't go too crazy with free samples -- I can attest to the fact that they WILL shut you down if you ask for too many sample shipments. I got a nice variety of drop-out regulators, temp sensors, amps, and more MCUs without issue, and can buy more if I need them (most ICs are pretty cheap...)

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I'm not sure if anyone's put together a colorful graphic like that, but all this information and a lot more can be found in the Datasheet for the chip-- see the product page http://www.ti.com/product/msp430g2231 and download the first PDF, "MSP430G2x21, MSP430G2x31 Mixed Signal Microcontroller (Rev. J)" and check out page 3.

 

Hmm actually looking at that datasheet, it looks like the G2231 only has 1 usable analogWrite() output.  That can be P1.2, P1.6 or P2.6 but only 1 of them can be used for that at a time.

 

All the "TA0.x" pins are analogWrite() capable *except* TA0.0 ones, like P1.1, P1.5.

 

Problem is though, I think the Software Serial library uses that P1.2 timer pin for its own work.  So you can't use analogWrite() and Serial at the same time.  I guess you need the 20-pin versions (and preferably the G2553 which has its own hardware serial) for maximum analogWrite() capability.  Probably not going to drive an RGB LED from one of those 14 pin or 20-pin G2xx2 (e.g. G2452) chips since you need 3 PWM outputs.

 

Thank you so much. So, it seems that i'll need to use G2553 with this RGB. But that's nice to know that the others works fine too, so that way I can use them with normal led and sensors and whatever I can imagine :D

 

I have put both LaunchPad chips on breadboards, it works fine. Push it in over a breadboard split and go nuts.

 

The key is to pull the RST pin UP, meaning to Vcc (as opposed to grounding it). Grounding RST is what resets the chip, so pulling it up via a pullup resistor (something like 47K ohm should do) brings the chip to life.

 

And hooking up Vcc and GND to the appropriate pins, of course.

 

From there, you can still program the chip, in place, with a Launchpad. Basically, you just use the emulation side of the Launchpad (those jumpers along the dashed line) and connect to Vcc, GND, RST, and TEST. Stick those connections in the breadboard at the right spots, connect the Launchpad to USB, and the chip will be visible to flash as if it were in the Launchpad socket.

 

Good luck!

 

PS: You can get sample chips from Texas Instruments, including the 553 and 452. So, you can get some spares, if you like. Don't go too crazy with free samples -- I can attest to the fact that they WILL shut you down if you ask for too many sample shipments. I got a nice variety of drop-out regulators, temp sensors, amps, and more MCUs without issue, and can buy more if I need them (most ICs are pretty cheap...)

 

I have already 2 chips working on a breadboard: one with a simples RGB led changing color (thanks to simpleavr that fixed the code :smile: ) and another with a 7segment display that simulates a dice.

The only problem I have here was with the jumpers that need to be in another position with energia when coding analog programs.

 

I have also a nice bounch of components by texas. They're awesome giving samples. And I heard that you may ask them one sample per month. If that's limit is true, I can ask them for a couple of MSP430 MCU's, bucause I don't order anything since December or January...

 

And thanks for the tips :D

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Hm, I will have to see if I can order anything again! I maxed out number of samples several times in quick succession as I worked through "basic" project ideas involving temp, amplification, etc. The voltage regulators are really nice, because I can regulate 3.3 and 5V from a single 9V battery (or my 12V car battery source) to do things like running the MCU and a 5V LCD. No worrying about voltage dividers or rolling your own transistor based regulation. I highly recommend their three-pin drop voltage regulators like the LM1084.

 

Thanks,

sutekh137

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They sent you and email informing that you have reached the samples limit?

 

I'm seeing it's datasheet of the voltage regalutaor and it seems really good. On the datasheet the reference is around the 8V input. Using a 9V input it deals with it fine too?

 

Next month I'll order one of each (3.3V and 5V) to try it out too :grin:

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They sent you and email informing that you have reached the samples limit?

 

I'm seeing it's datasheet of the voltage regalutaor and it seems really good. On the datasheet the reference is around the 8V input. Using a 9V input it deals with it fine too?

 

Next month I'll order one of each (3.3V and 5V) to try it out too :grin:

 

Yeah, it started by them asking for a note to justify, and then became a rejection after an order was accepted, saying I had requested too many samples recently. They're not wrong.  *smile*

 

I want to say the LM1084 allows inputs over a very wide range, at least up to 12V (I use a car battery, for example). I think I also got some LM1085s and LM1086s -- pretty much the same but I think they have different current limitations.  Looks like the LM1084 can handle 5 amps of output current, and input voltage can be dropped down from 2.6 to 27 volts. So it can handle a very large range.

 

As I said, I have used 6, 9, and 12v to run my 3.3/5v hybrid wirings. A lot of components out there work for 5V due to the Arduino boards running on that (at least a lot of them do).

 

You can also get the drop-out regulators in an "ADJ" flavor, meaning you can add your own resistors to make it drop down to whatever you wish.

 

Thanks,

sutekh137

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Thank you sutekh137 :)

 

I know I have that "ADJ" option, but if I can get all the other ones for free I'll try that 8-).

 

I'll buy a couple of 3.3V and 5V regulators to try to "feed" an MSP430 chip and a bounch of LEDs (from a USB cable flugged in the wall) to make a surprise to my girlfriend :D

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