Eight data bits, no parity bit, one stop bit — the default framing for almost every serial device you will meet.

Why is my serial output garbage?

Almost always a baud-rate mismatch. The giveaway is that the garbage is consistent rather than random. Try 115200 and 9600 first, then the neighbouring rates.

Is UART the same as RS-232?

The framing is the same; the electrical levels are not. UART on a microcontroller is 3.3 V or 5 V logic, while RS-232 uses ±3 to ±15 V with inverted polarity — connecting them directly needs a level shifter such as a MAX232.

RS-232 / Serial Decoder

Analyse serial framing, baud rate, parity and byte values.

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The rs232-decoder decoder is on the roadmap. The heavier binary and cryptographic parsers ship after the core text and token decoders — all of which are already live and working.

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What is the RS-232 / Serial Decoder?

An RS-232 decoder interprets asynchronous serial data by applying the framing rules — start bit, data bits, optional parity, stop bits — to recover the bytes transmitted on a UART link.

Asynchronous serial has no clock line, so both ends must agree on the bit rate in advance. Each byte is framed: an idle-high line drops for one start bit, then the data bits arrive least-significant first, then an optional parity bit, then one or two stop bits. The notation 8N1 means eight data bits, no parity, one stop bit — the near-universal default.

When the baud rate is wrong, the symptom is distinctive: consistent, repeatable garbage rather than intermittent errors. Because the receiver samples at fixed intervals, a mismatched rate misreads every byte the same way. Halving or doubling the rate is the first thing to try when a console prints nonsense.

RS-232 proper also defines electrical levels — ±3 to ±15 volts, with a logic 1 being the negative voltage — which is why connecting a 3.3 V microcontroller UART directly to a real RS-232 port damages it. The framing is identical; the voltages are not.