MSP430FR2633: I/O = "State held" in LPM3 /LPM4 / LPM3.5 / LPM4.5

Hideaki Nambu

Mastermind 9165 points

Part Number: MSP430FR2633

Hello,

Could you please tell me the meaning of the words "State held" in the LPM modes ?

What is the difference against the "On" in the AM mode ?

over 8 years ago

0 Clemens Ladisch over 8 years ago

Guru 317390 points

"On" means that the pins behave as configured in the digital I/O registers.

"State held" means that the pins keep their old configuration. This matters in LPMx.5, where the register contents are lost.

0 Hideaki Nambu over 8 years ago in reply to Clemens Ladisch

Mastermind 9165 points

Clemens,
Thank you very much for your response.
But I'm sorry, it is not clear for me still now.

Can I ask some more explanation ?
I could not understand the followings as the same meaning:
* "State held" means that the pins keep their old configuration.
* This matters in LPMx.5, where the register contents are lost.

And what is your extra point of the LPMx.5 ? The register defaults but the pin states are unchanged like output-low or pull-up-high ?

0 Clemens Ladisch over 8 years ago in reply to Hideaki Nambu

Guru 317390 points

Section 7.3.3 of the User's Guide says:

During LPMx.5 the I/O pin states are held and locked based on the settings before LPMx.5 entry. Note that only the pin conditions are retained. All other port configuration register settings such as PxDIR, PxREN, PxOUT, PxIES, and PxIE contents are lost.

0 Hideaki Nambu over 8 years ago in reply to Clemens Ladisch

Mastermind 9165 points

Clemens,
Very clear. Thank you very much.

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MSP430FR2633: I/O = "State held" in LPM3 /LPM4 / LPM3.5 / LPM4.5