Data transmission from MSP430F2619 to PC

janmay b c

... use the FT2232D chip to send data to the PC, 

but i  really am not able to make this scheme work.

Why not??

That really does sound like the simplest and most obvious way to do it!!

Lots of people manage to do this - where are you stuck??

How will i send the data to the PC (SPI or UART) 

PCs don't have SPI ports - so you can't use that directly.
A UART will go to the PC's COM port (or to a USB adaptor, if the PC doesn't have a real COM port).
But the FT2232D is exactly the chip you need to connect a UART to a PC via USB - so what's your problem?
and which pins do i need to bring out 

Obviously, you have to bring out the SPI pins if you want to use SPI, or the UART pins if you want to use a UART!!
( coz its better to know which pins will be required before i mutilate my PCB )

If your "project guide" insists that you use that board then, surely, it must be suitably equipped for the task that you have been set??
 I did some snooping around the internet and found that a level shifter is required in-between the MCU and PC

A PC COM port is RS232 - so you would need a "level shifter" (more precisely, an RS232 Transceiver) to connect that to your MCU.
But, again, if you're thinking of doing this then why not just use the FT2232; that's exactly what it's for! It effectively takes the place of the RS232 Transveicer for connecting via USB  to a "virtual" COM port on the PC!
 
FTDI

This device features two multi-purpose UART/FIFO controllers which can be configured individually in several different modes.  As well as a UART interface, a FIFO interface and the Bit-Bang IO mode of the 2nd generation FT232B and FT245B devices, the FT2232D offers a variety of additional new modes of operation including a Multi-Protocol Synchronous Serial Engine (MPSSE) interface which is designed specifically for synchronous serial protocols such as I2C, JTAG and SPI bus.




http://www.ftdichip.com/Products/ICs/FT2232D.htm

Well, I don't know what you've done to mess up the forum like that!!

Let's try again:

janmay b c

... use the FT2232D chip to send data to the PC,

but i  really am not able to make this scheme work.

Why not??

That really does sound like the simplest and most obvious way to do it!!

Lots of people manage to do this - where are you stuck??

How will i send the data to the PC (SPI or UART)

PCs don't have SPI ports - so you can't use that directly.

A UART will go to the PC's COM port (or to a USB adaptor, if the PC doesn't have a real COM port).

But the FT2232D is exactly the chip you need to connect a UART to a PC via USB - so what's your problem?

and which pins do i need to bring out

Obviously, you have to bring out the SPI pins if you want to use SPI, or the UART pins if you want to use a UART!!

( coz its better to know which pins will be required before i mutilate my PCB )

If your "project guide" insists that you use that board then, surely, it must be suitably equipped for the task that you have been set - surely??

Why are you not seeking advice & guidance on this from your "project guide"...?

I did some snooping around the internet and found that a level shifter is required in-between the MCU and PC

A PC COM port is RS232 - so you would need a "level shifter" (more precisely, an RS232 Transceiver) to connect that to your MCU.

But, again, if you're thinking of doing this then why not just use the FT2232; that's exactly what it's for!
It effectively takes the place of the RS232 Transveicer for connecting via USB  to a "virtual" COM port on the PC!

FTDI

This device features two multi-purpose UART/FIFO controllers which can be configured individually in several different modes.  As well as a UART interface, a FIFO interface and the Bit-Bang IO mode of the 2nd generation FT232B and FT245B devices, the FT2232D offers a variety of additional new modes of operation including a Multi-Protocol Synchronous Serial Engine (MPSSE) interface which is designed specifically for synchronous serial protocols such as I2C, JTAG and SPI bus.

http://www.ftdichip.com/Products/ICs/FT2232D.htm

Perhaps the simplest way to just connect a UART to a PC via USB is to use one of these:

Also available with bare wire ends:

The USB end just plugs into the PC, and appears as a COM port;

The other end just connects to the UART's logic-level pins.

Take care to use the correct version for your UART logic levels - 3.3V or 5V

janmay b c

How will i send the data to the PC (SPI or UART)

Most likely UART, since UART cards (or USB/USRT converters) are common, but SPI interfaces are special (and therefore expensive and rare) industrial stuff.

janmay b c

which pins do i need to bring out

The same you had used for stuffing the FTDI chip (basically, those USB/serial converters are nothing more than an FTDI-liek chip and an additional level shifter for RS232 output levels (if any).
If you want to connect to a real COM port ont he PC, you'll need a level shifter on the MSP side for the required RS232 signal levels. For 3V VCC, use the MAX3232 or similar.

janmay b c

If there are any other links/webpages/schematics that elucidate this scheme, please post them.

Did you search this forum? There have been several threads about this. You're not the first one wanting to attach an MSP to a PC :)

janmay b c

my guide wants results out of my current board

What one wants and what one gets are often two different things :) I have been asked to violate some physical laws during my IT courses too. I refused to, as I was afraid what the universe could do to me then. Still got my diploma. Sometimes you don't need to solve a task, you only need as good explanation why you didn't. :) (and providing an alternative solution gains extra points)

However, in your case, there is hope :)

Hi Mr Andy,

Thanks for your prompt response.

Before i explain my situation and well before the ever-helpful Mr 

Roberto Romano accuses my knowledge of MSP's to be microscopic :-). 

Here are the Facts:

1) I simply dont understand the datasheet of FT2232D, the problem is that i have 

copied the connections of the pins of FT2232D pins from an earlier design

 which used the FT2232D in FIFO mode.

Now, for fifo mode i need to connect 8 I/O pins of MCU to the FT2232D, 

in my case i have connected 6 (only god knows how i made this mistake during design !!)


2) There's no step-by-step kinda documentation for the FT2232D.

3) My project guide just wants to avoid the cost of making another board, thats it :-)


4) Till now i have installed the needed drivers and the FT2232D is being

 recognised as COMPORT15 and COMPORT16 in my device manager


All in all, my understanding of the FT2232D is not that great. And nobody in my institute is using it,

 infact i am the first to use a MSP430 over here!!, the rest work with the 8-bit PIC MCU.  But Thats not an

 valid excuse i know.

best wishes
janmay

Dear Sir,

Jens-Michael Gross

For 3V VCC, use the MAX3232 or similar.

Thanks for your prompt response.

best wishes

janmay

Dear Sir,

Jens-Michael Gross

For 3V VCC, use the MAX3232 or similar.

Thanks for your prompt response.

best wishes

janmay

janmay b c

I simply dont understand the datasheet of FT2232D

So just use one of the ready-made cable assemblies, then!

As I said, with those cables all you have to do is connect the wires to your UART pins, and plug the other end into your PC!
Simples!

Alternatively, you might look at one of the simpler FTDI chips - one that just does UART-to-USB (without the FIFO, etc).

Or look at one of the many modules using the FTDI chips.

Or any other manufacturer's USB-to-UART bridge chips...

My project guide just wants to avoid the cost of making another board

Again, why are you not getting your "guide" to actually guide you in this?!

the rest work with the 8-bit PIC

That's completely irrelevant!

The way you connect the MCU's UART pins to a UART-to-USB bridge is identical whether it's a PIC or an 8051  or just a plain 16550 UART.

The FTDI chips are so common that you must, surely, be able to find an examle somewhere...

 

Hi Andy,

Thanks for your quick response. Will ponder over the things you said.

Yes, the FT2232 does seem to be commonly used. Will go back,

do some reading and experimentation. Thanks.

best wishes

janmay

Why don't you just use one of the FTDI cables:

As previously mentioned, you just connect the wires direct to your UART pins - that's all there is to it!

Just make sure you use the correct voltage option. 

Hi Andy,

Thanks for your advice. Before i jump into any more hardware modifications, i want to get my code right.

If possible plese clear my following doubts:

I want to send 20(h) to the PC.This is how i am doing it.

UART initialization:

UCA0CTL1 = UCSSEL_1 | UCSWRST; // Clk = Aclk(32KHz), Reset = 1
UCA0CTL0 = UCMSB; // send MSB first
UCA0BR0 = 0x03; // select baud rate as 9600, 32kHz/9600 = 3.41
UCA0BR1 = 0x00;
UCA0MCTL = UCBRS1 + UCBRS0; // Modulation UCBRSx = 3 (Don't Know what this does
                                                      but every example prgm on UART has this)
UCA0CTL1 &= ~UCSWRST; // Reset = 0

Sending 20(h):

UCA0TXBUF = 0x20; // send 20(h)
   while (!(IFG2 & UCA0TXIFG));

1) What is meant by this "Modulation"?? i read the users guide,
but could not make out its purpose.

2) Is the sending part correct??
    
best wishes

janmay

janmay b c

UCA0BR0 = 0x03; // select baud rate as 9600, 32kHz/9600 = 3.41
UCA0BR1 = 0x00;
UCA0MCTL = UCBRS1 + UCBRS0; // Modulation UCBRSx = 3 (Don't Know what this does
but every example prgm on UART has this)

32kHz/9600 is 3.41, yet the baudrate divider is an integer (you cannot count to 3.41 clock pulses, you only know at the 4th clock pulse that you're too late).
So 32768/3 is 10922Bd, not 9600Bd.

The modulation now introdices a patter that for soem bits not 3, but 3+1 is used. If properly selected, some bits are too short (too-high baudrate) and some are too long (low baudrate), but the average is the desired baudrate and the bit edges fall not too far from the desired timing.

The clock module uses a similar mechanism for the DCO.

Dear Sir,

In layman terms, this modulation compensates for the 0.41 part and makes

sure that the baud rate remains 9600Bd, am i right?

and sir, are the init and sending part okay??

janmay b c

Before i explain my situation and well before the ever-helpful Mr 

Roberto Romano accuses my knowledge of MSP's to be microscopic :-). 

 Hey Janmay, lack of knowledge to complete this project signify you MUST get a couple of book with topic basic electronics and basic programming, after that I suppose you  also need a BASIC programming course on MSP, you confuse port register bit and what they mean. At almost port bit register need to be fully understood, where you can go whitout this? Is this your job? Ok we cannot solve for you.. so....

 You posted this question in Stellaris forum and I told you about your code is still wrong. Again no port initialization exist and without this knowledge base you cannot complete the project.

 Again I pointed that on how you settled spi cannot program precise phase relationship on AD9834 pairs, if you need to do sync rectification or IQ demodulator from them  to evaluate phase and amplitude of real and imaginary part of signals jiiter fail miserably integration and measurement.

 Again on FT2232 I suggested you to use a cable like the one Andy pictured to check FT interface is ok then proceed step by step checking MSP communication..

 I suggested to get an MSP board with USB and experiment and fully understand with code examples on that board, you answered a new pcb is making???

 I completed myself my thesis without screaming to professors how to write single chapter or paragraph....

 If you did'nt grasp knowledge of how to solve problem you never go to a solution, making a new pcb is not a good solution: new error can be added to.. best is to rewire the one you have then make the final version. Try insist other solve your miriad of single problem and this generate a bad set of ununderstood  and system block never can fit together.

 Regards

Roberto Romano

making a new pcb is not a good solution: new error can be added to.. best is to rewire the one you have

That, of course, depends on how much re-wiring is needed!