| ??? 04/20/07 02:59 Read: times |
#137584 - the original 8051 is the problem... Responding to: ???'s previous message |
Russell Bull said:
Rule#1 - get the code working first, then look at optimising. The way I have it configured when I posted it works, but not to my complete satisfaction. Looking at your code - there is no evidence of a ring buffer - where are the head and tail pointers? Address 08h represents my primary pointer which increments every time a new character is received. then DPL of dptr is set to the value stored at 08h. Later, when I want to use the buffer, I make another pointer equal to the value at 08h. With a circular (ring) buffer, you don't need flags - you compare the head and tail pointers to see if the buffer is empty,has data avail or full. I can agree, but again, we want to come out with working code. Assign symbolic names to ram and bits - makes your code easier to read. I never thought of that. Thanks. What is the problem in utilising internal ram? Use R0 or R1 instead of DPTR. It seems simple, but I only have 128 bytes of RAM, in which the majority of it is given to SFR's and the registers R0 to R7. It seems that I can reliably use addresses 30h to 7Fh. I want to minimize the logic in the serial routine so that I can have more clock cycles available for other tasks. push PSW push ACC push bank0_R0 mov r0,head_ptr mov a,SBUF clr RI mov @r0,a inc r0 ; ; add in test for end of buffer ; mov head_ptr,r0 pop bank0_R0 pop ACC pop PSW reti Wont your code overwrite several SFR's? It doesn't detect when the pointer reaches 7Fh. |
| Topic | Author | Date |
| if I could crunch my code... | 01/01/70 00:00 | |
| Optimisation | 01/01/70 00:00 | |
| the original 8051 is the problem... | 01/01/70 00:00 | |
| Duhh! | 01/01/70 00:00 | |
| again, I want to "crunch my code" | 01/01/70 00:00 | |
| starg with something that works. | 01/01/70 00:00 | |
| Did You Look at Movx @R0 ? | 01/01/70 00:00 | |
| Thanks (after I tried it LOL) | 01/01/70 00:00 | |
| data sheet | 01/01/70 00:00 | |
Hidden P2 Register? | 01/01/70 00:00 | |
| Simple,but no simpler | 01/01/70 00:00 | |
| Problem? | 01/01/70 00:00 | |
| save a few bytes by using JBC | 01/01/70 00:00 | |
| an alternative | 01/01/70 00:00 | |
| WRONG | 01/01/70 00:00 |