| ??? 05/15/09 16:29 Read: times |
#165387 - not really applicable Responding to: ???'s previous message |
Neil Kurzman said:
Many compilers use const instead of code. Actually, most compilers don't have a 'code' keyword. 'const' is a standard keyword, and the standard notes that it may be used to identify items for non-volatile storage. 'code' is a proprietary extension to accomodate the fact that the 8051 architecture has a distinct CODE address space. It would not be very useful for an 8051 compiler to use 'const' to mean CODE space, because you might also want to qualify things in other memory spaces as 'const' - in particular, if you had some non-volatile memory mapped into XDATA space (or, perhaps, a read-only XDATA-mapped peripheral) (In fact, Keil does have a facility to load 'const xdata' items into the Hex file so that they can be programmed into a PROM mapped into XDATA space) |
| Topic | Author | Date |
| C lang. question | 01/01/70 00:00 | |
| Confused | 01/01/70 00:00 | |
| re: | 01/01/70 00:00 | |
| Did you get the job? | 01/01/70 00:00 | |
| Do you _want_ the job? | 01/01/70 00:00 | |
| Same same | 01/01/70 00:00 | |
| Yes, that was exactly what I meant! | 01/01/70 00:00 | |
| re:job | 01/01/70 00:00 | |
| OR | 01/01/70 00:00 | |
| I wouldn't have thought so? | 01/01/70 00:00 | |
| Who knows | 01/01/70 00:00 | |
| not really applicable | 01/01/70 00:00 | |
| I agree | 01/01/70 00:00 | |
| Still missing the point. | 01/01/70 00:00 | |
| using 'const' for 'code' would be very bad | 01/01/70 00:00 | |
| Two examples | 01/01/70 00:00 | |
| Different issues | 01/01/70 00:00 | |
| architectual | 01/01/70 00:00 | |
| Actually irrelevant to the const keyword | 01/01/70 00:00 | |
| if it is irrelevant, then why ... | 01/01/70 00:00 | |
| Because they are not equivalent | 01/01/70 00:00 | |
| Exactly. | 01/01/70 00:00 | |
Standard mechanisms for extensions | 01/01/70 00:00 | |
| volatile applies to data - not functions | 01/01/70 00:00 | |
| Delay loops in 'C' (or any other HLL) | 01/01/70 00:00 |