When an unused port pin is left undefined or non-terminated, the floating voltage or shoot-through current on the pin can increase the overall current consumption.
Considerable additional supply current due to undefined input voltages.
This remark is issued when a port on the MSP430 device is not initialized/terminated:
To remedy this ULP rule violation, each and every port on the MSP430 device needs to be initialized/terminated. Each port pin should have the following:
P1DIR = 0xFF; P1OUT = 0x00;
P1SEL = 0xBE;
P1SEL2 = 0xEF;
See the rest of the code examples for all MSP430 devices here!
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Go to MSP430's e2e online forum!
If you are posting on the forums in relation to this rule, try using the tag "ULP_4.1"
Notice that ULP Advisor detects the number of ports & GPIO pins on the device basing strictly on the device number and does not have the knowledge on the actual package for the device. Therefore, it always assumes the largest package available to the device. In the event that a smaller package is actually used in the application, certain port pins might not be available on the device package. If this is the case, this remark can be safely ignored as these pins are internally terminated to ensure lowest power consumption and therefore the application is not required to configure/terminate these port pins.
For devices with Port 11 but no Port 12, ULP Advisor still checks for Port 12 initialization. This is a known bug and will be fixed in the upcoming release. At the moment, the workaround for this issue is to initialize Port 11 using Port F registers (16-bit wide).
For technical support please post your questions at http://e2e.ti.com. Please post only comments about the article Compiler/diagnostic messages/MSP430/10372 here. |