| ??? 07/06/05 08:50 Read: times |
#96668 - how far is it different Responding to: ???'s previous message |
Erik said: OK so you really think we (8052.com users) are in the position to make the rules? I would be happy to do so, see the "kitchen sink" thread :-)
if we discuss the rules, will they still be unwritten? :) Erik said: Of course not, although with the "added" SFRs (against the 8051) it seems there is a similar tendency: where there is dual DPTR, it is switched by bit 0 of AUXR1, which tends to be at A2h (at least for Philips and Atmel products). There are also other "unwritten rules" for '51 clones, e.g. the SFR bits are set to 0 at reset (if not undefined) (except for the ports), the extra features tend to be off by default, or, as you pointed out, the marking of XTAL1 and XTAL2 pins is somewhat "standard".
Adding a SFR for some function is, in my opinion, not breaking a "rule", thus many derivatives with "advanced features" are not rulebreakers. Joseph Hebert said: I think, (Erik can correct me), that the "standard" SFRs are there, but named differently and they are placed at a different address. Although one can object that from the point of view of the programmer this is only a matter of a definition file, but it seems to me, that this is really not necessary and as so, should be avoided in sake of simplicity when moving from clone to clone.
What about this is "unwritten?" I thought the standard SFRs were a fundamental tenet of the 51/52 definitions. Are you saying that there is a vendor selling ยต-controllers, calling them 8051s or 8052s, but without the standard SFRs? Jan Waclawek |
| Topic | Author | Date |
| unwritten rules in '51 design | 01/01/70 00:00 | |
| if we discuss the rules, will they still | 01/01/70 00:00 | |
| What do you mean "unwritten?" | 01/01/70 00:00 | |
| how far is it different | 01/01/70 00:00 | |
| yes and no | 01/01/70 00:00 | |
Then they are not there. | 01/01/70 00:00 | |
| yes, Joseph | 01/01/70 00:00 |