Single wire radio to charger communications method

DETAILED DESCRIPTION This invention is a method by which the charging status of a battery can be transmitted from a microprocessor in a phone or radio to a charger across a single wire interface.
The communication is accomplished by modulating the duty cycle of logic "high" signals across a predetermined pulse period.
The pulse period is subdivided into N increments.
By way of an example, if N=10 and the pulse width is 1 millisecond, each 1/10 of a millisecond is one division.
A word then corresponds to a specific relationship of the number of divisions that the line is high, versus the number of divisions the lines is low.
In other words, when the logic signal on the one wire interface is high for one-tenth of a pulse, this may correspond to a battery state of 0% to 30% charged, which should cause a red LED on a charger to illuminate.
In another case, if the line is high for two-tenths of a pulse, this may tell the charger that the battery is between 31% and 60% charged, causing the charger to light a yellow LED.
This invention is for use in systems where the charger acts as a slave to a phone or radio that has its own charging circuitry.