Datasheet

Table Of Contents
217
ATmega640/V-1280/V-1281/V-2560/V-2561/V [DATASHEET]
2549Q–AVR–02/2014
4. The addressed MCU will receive all data frames until a new address frame is received. The other Slave
MCUs, which still have the MPCMn bit set, will ignore the data frames.
5. When the last data frame is received by the addressed MCU, the addressed MCU sets the MPCMn bit and
waits for a new address frame from master. The process then repeats from 2.
Using any of the 5-bit to 8-bit character frame formats is possible, but impractical since the Receiver must change
between using n and n+1 character frame formats. This makes full-duplex operation difficult since the Transmitter
and Receiver uses the same character size setting. If 5-bit to 8-bit character frames are used, the Transmitter must
be set to use two stop bit (USBSn = 1) since the first stop bit is used for indicating the frame type.
Do not use Read-Modify-Write instructions (SBI and CBI) to set or clear the MPCMn bit. The MPCMn bit shares the
same I/O location as the TXCn Flag and this might accidentally be cleared when using SBI or CBI instructions.