MSP430G2553 — Flash +19% and RAM +57%

[rei-vilo]

The same blink sketch compiled executable inflates 19%, and RAM usage increases +57%.

This is especially critical for the MSP430G2553 with 512 bytes available!

• Using msp430/bin/msp430-size,

   text    data     bss     dec     hex filename
    758       0      14     772     304 Blink3.ino.elf with Energia 12

   text    data     bss     dec     hex filename
    900       0      22     922     39a Blink3.ino.elf with Energia 18 and MSP430 1.0.2

• Code

uint8_t myLED;

void blink(uint8_t pin, uint8_t times, uint16_t ms, bool level = true);

void setup()
{
    myLED = RED_LED;
    pinMode(myLED, OUTPUT);
}

void loop()
{
    blink(myLED, 3, 333);
    delay(1000);
}

void blink(uint8_t pin, uint8_t times, uint16_t ms, bool level)
{
    for (uint8_t i = 0; i < times; i++)
    {
        digitalWrite(pin, level ? HIGH : LOW);
        delay(ms >> 1);
        digitalWrite(pin, level ? LOW : HIGH);
        delay(ms >> 1);
    }
}

[robertinant]

Did you use the old or new compiler for this?

[rei-vilo]

I used the old compiler part of msp430-lg-core and went through releases 12 to 18 of Energia to check the size.

msp430-gcc (MSPGCC 20120406 (With patches: sf3540953 sf3559978)) 4.6.3 20120301 (mspgcc LTS 20120406 unpatched)

[robertinant]

platform.txt has it's optimization set to -O2. What sizes do you get if you change this to -Os for compiler.c.flags and compiler.cpp.flags

[rei-vilo]

I'm using embedXcode and both are set with -Os.

The issue isn't critical per se, as embedXcode gives me the flexibility to use the previous MSP430 package of Energia 12.

Everything is identical, except the release of the framework, 0.1.2 or 1.0.2.

• With Energia 12

/Applications/IDE/Energia.app/Contents/Java/hardware/tools/msp430/bin/msp430-g++ -w -c -Os -Wall -ffunction-sections -fdata-sections -mmcu=msp430g2553 -DF_CPU=16000000L -I/Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/0.1.2/variants/launchpad -I/Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/0.1.2/cores/msp430 -I/Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/0.1.2/cores/msp430/avr -I/Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/0.1.2/libraries -I/Applications/IDE/Energia.app/Contents/Java/libraries -DENERGIA=10610 -DARDUINO=10610 -DEMBEDXCODE=614 -DENERGIA_ARCH_MSP430 -DENERGIA_lpmsp430g2553 -D__MSP430G2553__     -fno-exceptions -fno-threadsafe-statics  /Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/0.1.2/cores/msp430/HardwareSerial.cpp -o Builds/cores/msp430/HardwareSerial.cpp.o

• With Energia 18 and MSP430 package release 1.0.2

/Applications/IDE/Energia.app/Contents/Java/hardware/tools/msp430/bin/msp430-g++ -w -c -Os -Wall -ffunction-sections -fdata-sections -mmcu=msp430g2553 -DF_CPU=16000000L -I/Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/1.0.2/variants/MSP-EXP430G2 -I/Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/1.0.2/cores/msp430 -I/Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/1.0.2/cores/msp430/avr -I/Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/1.0.2/libraries -I/Applications/IDE/Energia.app/Contents/Java/libraries -DENERGIA=10610 -DARDUINO=10610 -DEMBEDXCODE=614 -DENERGIA_ARCH_MSP430 -DENERGIA_MSP-EXP430G2553LP -D__MSP430G2553__     -fno-exceptions -fno-threadsafe-statics  /Users/ReiVilo/Library/Energia15/packages/energia/hardware/msp430/1.0.2/cores/msp430/HardwareSerial.cpp -o Builds/cores/msp430/HardwareSerial.cpp.o

[robertinant]

What numbers do you get with 1.0.1?

[rei-vilo]

Energia	text	data	bss	dec	hex
12	758	0	14	772	304
13	896	0	22	918	396
14	896	0	22	918	396
15	896	0	22	918	396
16	896	0	22	918	396
17	900	0	22	922	39a
18 / 1.0.1	900	0	22	922	39a
18 / 1.0.2	900	0	22	922	39a

[RickKimball]

Check out the -minrt linker flag combined with -Os compile time flag

http://forum.43oh.com/topic/5767-alternative-super-small-crt-for-msp430-elf-gcc-491/?p=50352

[edit] Of course that may break static initialization and ctors, but it will make it smaller[/edit]

[rei-vilo]

Results unchanged, 758 / 14 for Energia 12, 900 / 22 after.

Flash size isn't a big deal, question is about RAM. With 512 bytes, each byte counts!

Some projects fail to run on the MSP432G2553, unless I use Energia 12.

[robertinant]

This is only going to get worse with the new gcc compiler I am afraid..

[rei-vilo]

No problem, as long as I can keep and use the old one with embedXcode.

[robertinant]

Yes, we are going to support both the new and the old compiler with the same core.

[robertinant]

This was due to the -g flag being supplied and has been fixed in the upcoming release later this week.

Sketch uses 810 bytes (4%) of program storage space. Maximum is 16,384 bytes.
Global variables use 20 bytes (3%) of dynamic memory, leaving 492 bytes for local variables. Maximum is 512 bytes.