| ??? 01/19/05 09:04 Read: times |
#85277 - Use MASK rather than bit address Responding to: ???'s previous message |
As an answer also to the question given in a new thread: in both designs, all the 1-wire IOs are located on the same port. This gives an easy option to use a single mask in order to address individual lines/devices.
An asm example, not correct, just an illustration of the idea:
IO0 EQU 01h
IO1 EQU 04h
IO2 EQU 10h
....
mov r2,#IO0
call Reset1W
mov r2,#IO1
call Read1W
....
Reset1W:
mov a,r2
cpl a
anl P2,a ;pulsing line LOW
call Delay1
mov a,r2
orl P2,a ;pulsing line HIGH
call Delay2
mov a,P2
anl a,r2 ;sampling the input
ret ;test acc for zero to get the input bit
....
This scheme allows also manipulate the lines simultaneously (ORing the masks together), as suggested by Andy. Jan Waclawek |
| Topic | Author | Date |
| sbit | 01/01/70 00:00 | |
| I do not understand | 01/01/70 00:00 | |
| You mean Dallas 1-Wire? | 01/01/70 00:00 | |
| Re | 01/01/70 00:00 | |
| What's the problem? | 01/01/70 00:00 | |
| I think that... | 01/01/70 00:00 | |
| indirect bit addressing | 01/01/70 00:00 | |
| The same iButton on all 3? | 01/01/70 00:00 | |
| sbit | 01/01/70 00:00 | |
| access all 3 , one at a time | 01/01/70 00:00 | |
| I had the same problem | 01/01/70 00:00 | |
| Lets try again | 01/01/70 00:00 | |
| Need ? | 01/01/70 00:00 | |
| Why? | 01/01/70 00:00 | |
| There is always the switch statement | 01/01/70 00:00 | |
| something like this... | 01/01/70 00:00 | |
| Simultaneous example | 01/01/70 00:00 | |
| Use MASK rather than bit address | 01/01/70 00:00 | |
| Oooops, sorry... | 01/01/70 00:00 | |
| Multiple 1Wire | 01/01/70 00:00 | |
| How to post code, and possible hang-up | 01/01/70 00:00 | |
| simultaneous? | 01/01/70 00:00 | |
| would even be better | 01/01/70 00:00 | |
If it worked! | 01/01/70 00:00 |