| ??? 03/03/08 03:47 Read: times |
#151774 - More details... Responding to: ???'s previous message |
Oh I think I miss out the error details. The uC can send out correct data as I verified with my Visual C++ program. The data is correct as per my MODBUS RTU program written in the Visual C++. Till then, I am suspecting the timing issue. Do correct me if I am wrong. The DS89C450 only have a 8 bit serial buffer which there might some delay during the transmission between each bytes. This delay which is long than 3.5 char which make the transaction terminated. So I am working on how to store the whole MODBUS RTU serial buffer before sending out in whole string. Let me read through your code below to find more clues. Thanks. |
| Topic | Author | Date |
| MODBUS RTU for 8051/DS89C450 | 01/01/70 00:00 | |
| How to post source code | 01/01/70 00:00 | |
| Formatted Source Code | 01/01/70 00:00 | |
| Looks like translated PIC code! | 01/01/70 00:00 | |
| So where is the problem? | 01/01/70 00:00 | |
| More details... | 01/01/70 00:00 | |
| How did you test your VC++ app...? | 01/01/70 00:00 | |
| uC -> RTU Slave (OK) ; RTU Slave -> uC (FAIL) | 01/01/70 00:00 | |
| RE:8 bit buffer | 01/01/70 00:00 | |
| Problem? | 01/01/70 00:00 | |
RE:8 bit buffer | 01/01/70 00:00 | |
| RTU Communication is working! | 01/01/70 00:00 |