What does the ".bss" command do in MSP430 assembly code? For example what does ".bss beep_cnt,2" do with the variable beep_cnt2?
.bss beep_cnt,2 ; beeper flag
.bss delay_cnt,2 ; delay flag
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1If it has anything in common with x86 .bss, it declares uninitialized memory. – Linuxios Oct 27 '12 at 15:04
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I'm using the TI MSP430g2553. http://www.ti.com/product/msp430g2553. Not sure if it's the same as x86 – user1779429 Oct 27 '12 at 15:17
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Not the same as x86, just if it means the same thing as in x86. – Linuxios Oct 27 '12 at 20:42
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what assembler are you using? – old_timer Nov 01 '12 at 00:41
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The term BSS is universal in assembly and C programming, across operating system no less. Core concept stuff, originally an acronym for "Block Started by Symbol" with a tongue-in-cheek version of Better Save Space. Goes back to the mid 1950s, started by an IBM 704 assembler and adopted into Fortran and flung from there. The wikipedia article has the history. Not otherwise mentioning the effort to get rid of globals over the past 20 years.
So it is reserving two bytes in the data segment that's zero-initialized at startup.
Hans Passant
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