| ??? 11/04/10 07:14 Modified: 11/04/10 07:18 Read: times |
#179476 - Can it? Responding to: ???'s previous message |
Richard Erlacher said:
The initial issue was to determine whether the MAX232 was properly functional. That can be done with a voltmeter Can it? A voltmeter wouldn't show things like excessive ripple or glitches on the supplies. But it is the obvious first test to make: if the reading is bad, then that's obviously a (the?) fundamental problem; but, if the reading looks good, then further investigation is needed. and further, seems it hasn't been done. Indeed If ... the device produces valid RS232 levels when its logic inputs are driven to +5 or Gnd, and produces valid logic levels when its RS232 inputs are driven to valid RS232 levels, e.g. V+ and V-, that answers the question about the MAX232, doesn't it? Not fully - again, it won't show things like ripple, glitches, or seriously slow rise/fall times. Again, it is (or should be) an obvious first test, but it does not give a complete answer |
