What the hell is going with RST on msp430g2553

After succesfull debug of my project with msp430g2553 (not launchpad) I faced with a problem on standalone run.

Due do datasheet, /RST pin pull-uped with 47k resistor to VCC. No success.

Than I pulled-down /RST to GND with 2,2nF capacitor without any effect.

After some googling I also soldered 0,1 uF capacitor between GND and VCC but still circuit don't work out of debug.

During the debug /RST has voltage level 3,1 V, in standalone run - 0. It is obvious that problem is there, but how to pull it up correctly?

UPD I also tried capacitors 100n, 4,7uF and resistors 1k, 10k, 0k (direct wire) and source circuit from battaries but with no luck. In debug mode program works perfectly in any of such RC's.

As a programmer I use Launchpad f5529. 

23 Replies

  • In reply to Sergii Matsiievsky:

    Quote from p.161 in davies08_MSP430 Microcontroller Basics:

    ``This is a classic example where any problem will probably not arise during early testing. The connections to the debugger usually include the RST/NMI pin and the output impedance of the interface pod is often low enough to suppress any noise picked up on the board. The sensitivity to noise appears only when the debugger is disconnected.''
  • In reply to small_stone_head:

    The connection at RST is the one I would also check first if the MSP does not start to run the application. Maybe the capacitor is connected to GND, but the resistor does not have a proper connection to DVcc, so RST is floating with an unconnected debugger...?

  • I have the same problem with an MSP430g2001 custom board.   I can download a program using CCS via TI FET, single step, and all is well.   When the spy by wire emulator is disconnected, the code does not run and based on the power consumption it looks like the processor is held in reset.

    47K pullup with a 2.2nF per the TI ref des and app notes.

    Any suggestions?