This page can show curves and timing for different serial communications formats. It is designed to be a help when doing software uart's and programming infared transmitters and receivers.
The program has support for the following formats:

Ordinary async. communication (RS232)
User specified async. communication (databits, parity, stopbits, lsb/msb first)
IR communication based on puls or space width modulation (i.e. Sony SIRCS)
IR communication based on biphase modulation (i.e. Philips RC5)

Reading and using the drawing

The drawing has many bits of information. It can be zoomed with the vertial slider at the right side. When zoomed it is possible to adjust what parts is shown with the horizontal slider (only visible when zoomed).

It show's vertial yellow lines (or marks) to mark the boundary between bits
It can show a horizontal yellow line to mark the voltage zero point (only on Async formats)
It can show cyan marks to mark the center of bits (only on Biphase formats)
It will show bitnames, but only when there is space for it (use the zoom function to make space)
It will show vertial red lines to mark the start of each byte or data element
A timescale is shown at the bottom of the drawing, to get more exact timings use the "Show time to bits" checkmark, this will list a table with all time values

Input fields

Only some of these fields are show at a time.

Baud	Specify baudrate, a lot of standard baudrates are listet. When "other" is selected, one more "baud" field is shown and any baud value can be typed in this field (up to 10Mbaud)
Bits	Databits in communication, ascii requires 7 bits
Parity	Parity is used as a simple check on the data validity (only for odd/even)
Stop bits	Stopbits signal the end of a byte and can give the receiver time to do some processing
MSB first	Send MSB (highest number bit) first
High level	Line level for 1-bit value, this level can be lover that "Low level"
Low level	Line level for 0-bit value, this level can be higher than "High level"
Text	Ascii text to encode, the bytes are clipped to specified number of bits
Data	Expression with data, this makes it possible to specify 9-bit values (i.e 314 is a 9-bit value)
IR subformat	When same protocol has multiple formats, they can be selected here
Manufactur	Manufactur code
Address/type	Equipment type
Command	Command to equipment
Show time to bits	Show detailed timing of each databit

Other pages

MPU Support list where MiscEl can help when working with microprocessors

MiscEl: Serial communication

Reading and using the drawing

Input fields

Other pages