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Hi there, Do you guys mind to briefly explain the difference between Macro and Subroutine? At what condition, it is a must to use Macro or at what condition it is desired to use Macro? Thanks in advance. __________________________________ Celebrate Yahoo!'s 10th Birthday! Yahoo! Netrospective: 100 Moments of the Web http://birthday.yahoo.com/netrospective/ |
Macro VS Subroutine
Started by ●March 8, 2005
Reply by ●March 8, 20052005-03-08
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Hello, To do quick: Macro are remplaced at compile time. This means each time you call a macro in your code, the compiler will "copy/paste" all the lines of the macro in the code. A subroutine is different in that, it's written once and it occupies memory code once, you just pass arguments and retrieve results at run time. In both case the purpose is to shorten the code size when you write the program. But the result is very different, after compiling, in term of code space occupation. Hope this helped ! Vince -----Original Message----- From: Devon Lee [mailto:] Sent: mardi 8 mars 2005 16:04 To: Subject: [piclist] Macro VS Subroutine Hi there, Do you guys mind to briefly explain the difference between Macro and Subroutine? At what condition, it is a must to use Macro or at what condition it is desired to use Macro? Thanks in advance. __________________________________ Celebrate Yahoo!'s 10th Birthday! Yahoo! Netrospective: 100 Moments of the Web http://birthday.yahoo.com/netrospective/ to unsubscribe, go to http://www.yahoogroups.com and follow the instructions Yahoo! Groups Links |
Reply by ●March 8, 20052005-03-08
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macros put the code "inline". Faster than a jump to a subroutine, but if you use it several times in your code, you eat up code space. You have to judge the tradeoffs. --- Devon Lee <> wrote: > Hi there, > > Do you guys mind to briefly explain the difference > between Macro and Subroutine? At what condition, it > is > a must to use Macro or at what condition it is > desired > to use Macro? > > Thanks in advance. > > __________________________________ > Celebrate Yahoo!'s 10th Birthday! > Yahoo! Netrospective: 100 Moments of the Web > http://birthday.yahoo.com/netrospective/ > __________________________________ Celebrate Yahoo!'s 10th Birthday! Yahoo! Netrospective: 100 Moments of the Web http://birthday.yahoo.com/netrospective/ |
Reply by ●March 8, 20052005-03-08
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A MACRO equates a line or lines of code to a simple phrase or even word. Macros can make it faster and easier to write code that is repeated several times in a program. The main problem with MACROS as I see it is, they hide what the code is doing and the size of the code from the programmer. This can be bad if you are trying to write tight code for overall program size purposes because at a glance you may not remember what the MACRO consisted of. A macro by its nature would be used several times throughout the program as a short form of writing that same piece of code. A subroutine is typically a CALLABLE routine that is used by the program in many areas. You would write it once and call it wherever you need it. Personally when in a team programming envronment I would ask that the team not use MACROS, but your mileage may vary. --- In , Devon Lee <devonsc@y...> wrote: > Hi there, > > Do you guys mind to briefly explain the difference > between Macro and Subroutine? At what condition, it is > a must to use Macro or at what condition it is desired > to use Macro? > > Thanks in advance. > |
Reply by ●March 10, 20052005-03-10
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Sorry for my late reply. Thanks for the explanation regarding the Macos and the Subroutine. Thanks a lot. __________________________________ |
Reply by ●March 10, 20052005-03-10
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--- In , allenbv1 <no_reply@y...> wrote: > > > A MACRO equates a line or lines of code to a simple phrase or even > word. Macros can make it faster and easier to write code that is > repeated several times in a program. > > The main problem with MACROS as I see it is, they hide what the code > is doing and the size of the code from the programmer. This can be > bad if you are trying to write tight code for overall program size > purposes because at a glance you may not remember what the MACRO > consisted of. A macro by its nature would be used several times > throughout the program as a short form of writing that same piece of > code. > > A subroutine is typically a CALLABLE routine that is used by the > program in many areas. You would write it once and call it wherever > you need it. > > Personally when in a team programming envronment I would ask that the > team not use MACROS, but your mileage may vary. There are processors where the call stack is tiny - like 2 levels. Whether this makes macros more desireable is an interesting point. However, using macros to hide the vagaries of hardware is my favorite use. I remember many years ago developing hardware to interface a DAT tape drive to an 8085. Someone else was supposed to do the application code but they kept complaining that the hardware didn't function. I wrote a set of macros to handle the tape drive and the interrupt system. Then the discussions re: did the hardware work were cut short. Here's the library, get on with the application! I have also used macros to create complex data structures. One was a huge lighting control project covering maybe 400k sq ft of office space. The data structure was all you might expect from having multiple buildings, multiple lighting panels of different capacities per building, circuits arranged in odd ways on the panels and a desired result of creating blocks somewhat related to occupancy and schedule for turn-off according to user needs. I am a big fan of macros and have been since I first created pseudo instructions for doing boolean algebra on an IBM 1130 back in 1970. My favorite guide for macros comes from the CP/M world: http://www.cpm.z80.de/manuals/mac.pdf There are a number of hardware hiding macros described. > --- In , Devon Lee <devonsc@y...> wrote: > > Hi there, > > > > Do you guys mind to briefly explain the difference > > between Macro and Subroutine? At what condition, it is > > a must to use Macro or at what condition it is desired > > to use Macro? > > > > Thanks in advance. > > |
