| ??? 02/17/03 22:14 Read: times |
#39284 - How to read eithe LATCH or PORT directly |
Each portpin on an 8052 is latched.
Most instructions read the port (mov a,P1). There are read-modify-write instructions (clr P1.0), which read the latch, make a modificateion and write it back to latch and port. There is a risk, if something like a bipolar transistor's base is connected to the aedequate pin. Then it will read 0, even if driven 1, if mov a,P1 is used. But how can I read the latch? Nigel |
| Topic | Author | Date |
| How to read eithe LATCH or PORT directly | 01/01/70 00:00 | |
| RE: How to read eithe LATCH or PORT directly | 01/01/70 00:00 | |
| RE: How to read eithe LATCH or PORT directly | 01/01/70 00:00 | |
| RE: How to read eithe LATCH or PORT directly | 01/01/70 00:00 | |
| RE: How to read eithe LATCH or PORT directly | 01/01/70 00:00 | |
RE: How to read eithe LATCH or PORT directly | 01/01/70 00:00 |