M306V5ME-XXXSP Datasheet, PDF (130/262 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER and ON-SCREEN DISPLAY CONTROLLER

MITSUBISHI MICROCOMPUTERS
M306V5ME-XXXSP
M306V5EESP
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER
and ON-SCREEN DISPLAY CONTROLLER
s Bit 4: I²C-BUS interface i interrupt request bit (PIN)
This bit generates an interrupt request signal. Each time 1-byte data is transmitted, the state of the
PIN bit changes from “1” to “0.” At the same time, an interrupt request signal is sent to the CPU. The
PIN bit is set to “0” in synchronization with a falling edge of the last clock (including the ACK clock) of
an internal clock and an interrupt request signal occurs in synchronization with a falling edge of the
PIN bit. When detecting the STOP condition in slave, the multi-master I²C-BUS interface interrupt
request bit (IR) is set to “1” (interrupt requested) regardless of falling of PIN bit. When the PIN bit is “0,”
the SCL is kept in the “0” state and clock generation is disabled. Figure 2.11.41 shows an interrupt
request signal generating timing chart.
The PIN bit is set to “1” in any one of the following conditions.
• Writing “1” to the PIN bit
• Executing a write instruction to the I²Ci data shift register or the I²Ci transmit buffer register (See note).
• When the ESO bit is “0”
• At reset
Note : It takes 8 BCLK cycles or more until PIN bit becomes “1” after write instructions are executed
to these registers.
The conditions in which the PIN bit is set to “0” are shown below:
• Immediately after completion of 1-byte data transmission (including when arbitration lost is detected)
• Immediately after completion of 1-byte data reception
• In the slave reception mode, with ALS = “0” and immediately after completion of slave address or
general call address reception
• In the slave reception mode, with ALS = “1” and immediately after completion of address data reception
s Bit 5: bus busy flag (BB)
This bit indicates the status of use of the bus system. When this bit is set to “0,” this bus system is not
busy and a START condition can be generated. When this bit is set to “1,” this bus system is busy and
the occurrence of a START condition is disabled by the START condition duplication prevention func-
tion (See note).
This flag can be written by software only in the master transmission mode. In the other modes, this bit is
set to “1” by detecting a START condition and set to “0” by detecting a STOP condition. When the ESO bit
of the I²Ci control register is “0” and at reset, the BB flag is kept in the “0” state.
s Bit 6: communication mode specification bit (transfer direction specification bit: TRX)
This bit decides the direction of transfer for data communication. When this bit is “0,” the reception
mode is selected and the data of a transmitting device is received. When the bit is “1,” the transmission
mode is selected and address data and control data are output into the SDA in synchronization with
the clock generated on the SCL.
When the ALS bit of the I²Ci control register is “0” in the slave reception mode is selected, the TRX bit
___
is set to “1” (transmit) if the least significant bit (R/W bit) of the address data transmitted by the master
___
is “1.” When the ALS bit is “0” and the R/W bit is “0,” the TRX bit is cleared to “0” (receive).
The TRX bit is cleared to “0” in one of the following conditions.
• When arbitration lost is detected.
• When a STOP condition is detected.
• When occurence of a START condition is disabled by the START condition duplication prevention
function (Note).
• With MST = “0” and when a START condition is detected.
• With MST = “0” and when ACK non-return is detected.
• At reset
Rev. 1.0
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