Timeline for What is the serial protocol commonly used over RS-232 (among other links) and where did it come from?
Current License: CC BY-SA 4.0
8 events
| when toggle format | what | by | license | comment | |
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| May 30, 2023 at 20:51 | comment | added | dave | And that's how "one and half bits" is not a weird thing, it's just a length of time. | |
| May 30, 2023 at 19:02 | comment | added | chux | @SottoVoce Yes a stop bit is needed when there is scant idle time between data "bytes" and data's MSbit is zero. Recall the idle condition is the same level as a stop bit. IAC, the stop bit does not time the synchronization. Sync is due to the start bit edge, which is ready to to be detected as soon as just after the 0.5 the stop bit. In essence a stop bit is simply a minimum idle time after the data. | |
| May 30, 2023 at 18:36 | comment | added | Sotto Voce | @chux-ReinstateMonica The start bit can't be a transition unless the stop bit is the opposite voltage polarity and is (required to be) present. It takes both the stop and start bits to guarantee a transition. | |
| May 30, 2023 at 15:10 | comment | added | chux | @jpa "transmitting 0x00 would have no transitions" --> More like: the start bit itself is a transition. Stop bit (at least 0.5 of a stop bit) is important for synchronization to cope with a sending rate slightly above the receiving sample rate. Synchronization happens with the start bit edge. | |
| May 30, 2023 at 8:51 | comment | added | jpa | Stop bit is also important for synchronization. Otherwise transmitting 0x00 would have no transitions and the clock phase would drift. | |
| May 30, 2023 at 1:02 | history | edited | dave | CC BY-SA 4.0 | added 208 characters in body |
| May 30, 2023 at 0:53 | history | edited | dave | CC BY-SA 4.0 | added 208 characters in body |
| May 30, 2023 at 0:35 | history | answered | dave | CC BY-SA 4.0 |