SparkFun Forums 

Where electronics enthusiasts find answers.

Discussions on how to get your MSP JTAG programmer up and running.
By 142536789
#169397
Hi, I'm trying to set up a Hardware UART from my PC to my MSP430G2553. I need the HW UART because it's faster than the software UART which has problems when going faster than 9600 b/s. I need the bandwidth so I can set up a 100 kHz oscilloscope.

I have DE-9 RS-232 port available on my PC, but from my understanding the serial port has a 12V logic level and the MSP430 uses 3.3V.

What adapter should I use?

Also, how do I program a MSP430 without a launchpad? The user's hardware guide says it's possible via JTAG or UART but doesn't go over the details.
By UhClem
#169418
You can use any RS-232 level shifter. You could build one using the MAX3232 or even something built from discrete components like this SparkFun shifter:


If you don't have any programming hardware at all (the Launchpad is cheap so you should get one) then you can use the bootstrap loader (BSL). Details vary between devices so you will have to look at the data sheets to see how to connect.
By 142536789
#169433
Thanks so much for the help guys!

I have the launchpad for the MSP430G2553, I'd just like to be able to program the MSP430 without it. I'll be using it in conjunction with a C2000 launchpad, the C2000 controls the motors and does the number crunching while the MSP430 takes some of the monotonous tasks off it's hands. It's a pretty complex project and I'm still finishing up the code for the MSP430 so I'm always updating it. I'd like to send data (wirelessly) to the C2000 and have it program the MSP430 via UART, JTAG or BSL. Preferably UART. So that way I don't have to dig it out of the circuit and put it back in the Launchpad, then transplant it back to the circuit to test it.
By UhClem
#169434
It sounds like what you require is a bootloader like that shown in TI application note SLAA600. Program the msp430 once and then later updates can be done over any data link you care to use.

There is no requirement to remove the IC from the circuit to reprogram it with the Launchpad, just connect three wires from the Launchpad and you are done. (Assuming the msp430 has its own power, if not then you need four wires.)