Transmission and reception methods for a binary signal on a serial link

A method of transmitting a plurality of bits over a serial link that is capable of taking two different states respectively associated with two possible logical values of the transmitted bits, the method comprising:

• starting from a transmission start time of a start bit and up to expiration of a first portion of a bit time associated with the start bit, using a transmitter to place the link in one of the two different states depending on a logical value of the start bit;
• upon expiration of the first portion of the bit time associated with the start bit, using the transmitter to generate a first additional transition over the link so as to place the link in the other one of the two different states up to an expiration of the bit time associated with the start bit, wherein a duration of the first portion is based on a speed of transmission
• starting from a transmission start time of an other bit of the plurality of bits and up to expiration of a period counted starting from the transmission start time of the start bit and equal to a sum of all bit times associated with earlier bits preceding the other bit and of a second portion of the bit time associated with the other bit, placing the link in one of the two different states depending on the logical value of the other bit;
• and
• upon the expiration of the period, generating a second additional transition over the link so as to place the link in the other one of the two different states up to an expiration of the bit time associated with the other bit.

A method for receiving a plurality of bits carried over a serial link that is capable of taking two different states that are associated with two possible logical values, the method comprising:

• using a receiver capable of receiving at a plurality of different speeds of transmission to detect a first transition between the two states of the link, the first transition occurring at a time after a reception start time of a start bit;
• using the receiver to determine a first period spanning from the reception start time to a time of occurrence of the first transition, a reception end time of the start bit being separated from the time of occurrence of the first transition by a first additional period that is equal to a first predetermined portion of the first period, wherein a duration of the first period is based on a speed of transmission of the plurality of different speeds of transmission;
• detecting the speed of transmission based on the duration of the first period;
• and
• receiving additional bits of the plurality of bits based on the detected speed of transmission.

A method of communicating using a serial link, the method comprising:

• using a transmitter capable to transmit at a plurality of different speeds of transmission to transmit an initial portion of a start bit for a first time period, the start bit having a start bit time, wherein the first time period is based on a selected speed of transmission of the plurality of different speeds of transmission, and wherein a duration of the first time period indicates the selected speed of transmission;
• using the transmitter to transmit an additional portion of the start bit having a second time period, the additional portion having an inverse value of the initial portion and the start bit time being equal to a sum of the first time period and the second time period;
• and
• after the start bit time, using the transmitter to transmit a plurality of useful bits, each of the useful bits having a useful bit time, the start bit time being longer than the useful bit time and being an integer multiple of the useful bit time.