| ??? 08/03/11 18:01 Read: times  | 
#183181 - probably Responding to: ???'s previous message  | 
...monovibrator is used to produce 'Drive enable' signal for 485 transceiver chip ( pulse with one byte length, restarted by any passive to active level edge) - i suppose there is not used any additional signal from RS232 side - so converter is transparent for software (only TX,Rx and Gnd used).
 In this case schematic is highly desirable for right suggestions. There are 3 scenarios may be: - Tx input of converter is high impedance (>10 kiloohm) , in this case 1 kiloohm resistor is ok; - Tx input of converter is something like MAX232 with input about 3 kiloohm , in this case recomended value is about 2 kiloohm ; - Tx input is low impedance ( but not optron) , i think best solution is to change converter; Anyway - schematic is needed. regards  | 
| Topic | Author | Date | 
| Problem with RS232/RS485 converter... | 01/01/70 00:00 | |
| More info please | 01/01/70 00:00 | |
| probably | 01/01/70 00:00 | |
| more info... | 01/01/70 00:00 | |
| yes,i think | 01/01/70 00:00 | |
| input impedance | 01/01/70 00:00 | |
| i'm wrong | 01/01/70 00:00 | |
| what is the right value? | 01/01/70 00:00 | |
| did You tryed capacitor? | 01/01/70 00:00 | |
| thanks... | 01/01/70 00:00 | |
| it works...! | 01/01/70 00:00 | |
| congrats | 01/01/70 00:00 | |
| shape | 01/01/70 00:00 | |
| dont | 01/01/70 00:00 | |
| It is OK. | 01/01/70 00:00 | |
| Hints... | 01/01/70 00:00 | |
| schema | 01/01/70 00:00 | |
| Repair... | 01/01/70 00:00 | |
| transils... | 01/01/70 00:00 | |
| RS485 | 01/01/70 00:00 | |
| Sample Schematic | 01/01/70 00:00 | |
| Thank you very much for the schema... | 01/01/70 00:00 | |
| AVX varistors... | 01/01/70 00:00 | |
| capacitor | 01/01/70 00:00 | |
| capacitors... | 01/01/70 00:00 | |
| GNDs | 01/01/70 00:00 | |
| 1992 | 01/01/70 00:00 | |
| Thanks... | 01/01/70 00:00 | |
                                 Links...        | 01/01/70 00:00 | 



