DATA TRANSFER METHOD AND APPARATUS FOR COMMUNICATION BETWEEN A PERIPHERAL AND A MASTER

摘要

Data transfer apparatus (211,213) for a radiotelephoneperipheral using a time multiplexed data bus for communicationwith a bus master of the radiotelephone (201) couples peripheraldevices external to the radiotelephone (201) and other userinformation inputting devices, such as a handset (203) for a cellularmobile radiotelephone, to the radiotelephone's central processor andspeech processor (207). The data transfer apparatus generates timeslots in frame formats in which the information is sent over the databus. The entire message, information bits and the header, sent in atime slot from a peripheral device to the bus master is used todetermine bus contention. Bus contention resolution during thestart-up of data bus operation sets the priority with respect to otherdata transfer apparati with which a peripheral device's data transferapparatus is able to access the bus during normal operation.