Flash and RAM usage

This is where developers can exchange ideas and ask questions relevant to the DM42 firmware.

Please note that Swiss Micros staff are unable to provide answers here as a general rule. This is intended as a community-driven forum.
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Over_score
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Flash and RAM usage

Post by Over_score »

In the file https://github.com/swissmicros/DM42PGM/ ... program.ld we find the following line:

Code: Select all

FLASH   (rx) : ORIGIN = 0x08050000, LENGTH =  704K
What is the use of the flash memory from 0x08000000 to 0x0804FFFF (320K) in a DM42?
If my program + constant data is bigger than 704K (from 0x08050000 to 0x080FFFFF), can I change the ORIGIN and LENGTH values in that file?

Another line in that file is:

Code: Select all

RAM    (xrw) : ORIGIN = 0x10000000, LENGTH =    8K
Why only 8K when the RAM size is 32K at this location?

TIA
Martin
DM42 SN00284 running free42 & SN03835 running WP43S, DM15L, HP41CV, HP42S, HP35s, WP34S, HP Prime
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Over_score
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Re: Flash and RAM usage

Post by Over_score »

Michael and/or David? Any hint?
DM42 SN00284 running free42 & SN03835 running WP43S, DM15L, HP41CV, HP42S, HP35s, WP34S, HP Prime
David
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Joined: Fri Apr 07, 2017 7:32 am

Re: Flash and RAM usage

Post by David »

Those are regions used by DMCP.
If your program needs more flash, you can use QSPI (first 2000kB region is available to user program).
If your program needs more static RAM, allocate some data from heap to relieve static RAM usage or reconfigure heap usage in linker script to get another static RAM region.

Note that if you want faster response to such questions, send me an email. Please, understand I have limited amount of time and I'm not able to answer general programming questions (e.g. how to modify linker script).
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Over_score
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Re: Flash and RAM usage

Post by Over_score »

Thank you, David.
I understand that you have limited time for this type of question and I think your answer is clear enough for me to proceed. Thank you again.
DM42 SN00284 running free42 & SN03835 running WP43S, DM15L, HP41CV, HP42S, HP35s, WP34S, HP Prime
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