380
CHAPTER 22 I
2
C
Note:
The AACKX, INTS, and WUE bits in the IBCR00 register are set to "0" and cannot be written to
either when I
2
C operation is disabled (ICCR:EN = 0) or when a bus error occurs (IBSR:BER = 1).
bit2
SPE:
Stop detection interrupt
enable bit
This bit enables or disables stop detection interrupts.
• A stop detection interrupt request is generated if this bit and the IBCR00:SPF bit are both "1".
Setting the bit to "0": Disables stop detection interrupts.
Setting the bit to "1": Enables stop detection interrupts.
bit1
WUF:
MCU standby-mode
wakeup interrupt
request flag bit
This bit is used to detect MCU wakeup from a standby mode (stop or watch mode).
• A wakeup interrupt request is generated if this bit and the IBCR00:WUE bit are both "1".
• This bit is set to "1" if a start condition is detected with the wakeup function enabled (IBCR00:WUE =
1).
Setting the bit to "0": Clears itself (changes the value to "0").
Setting the bit to "1": Leaves its value unchanged without affecting the operation.
• The bit returns "1" when read by a read-modify-write operation.
bit0
WUE:
MCU standby-mode
wakeup function
enable bit
This bit enables or disables the function to wake up the MCU from standby mode (stop or watch mode).
Setting the bit to "0": Disables the wakeup function.
Setting the bit to "1": Enables the wakeup function.
• If a start condition is detected in stop or watch mode when this bit is "1", a wakeup interrupt request is
generated to start I
2
C operation.
Note:
•
Write "1" to this bit immediately before the MCU enters the stop or watch mode. To
ensure that I
2
C operation can restart immediately after the MCU wakes up from stop
or watch mode, clear (write "0" to) this bit as soon as possible.
• When a wakeup interrupt request occurs, the MCU wakes up after the oscillation stabilization
wait time elapses. To prevent the data loss immediately after wakeup, therefore, the SCL0
must rise as the first cycle and the first bit must be received as data after 100
μ
s (assuming that
the minimum oscillation stabilization wait time is 100
μ
s) from the wakeup due to the start of
I
2
C transmission (upon detection of the falling edge of SDA0).
• During a MCU standby mode, the status flags, state machine, and I
2
C bus outputs for the I
2
C
function retain the states they had prior to entering the standby mode. To prevent a hang-up of
the entire I
2
C bus system, make sure that IBSR0:BB = 0 before entering standby mode.
• The wakeup function does not support the transition of the MCU to stop or watch mode with
IBSR0:BB = 1. If the MCU enters stop or watch mode with IBSR0:BB = 1, a bus error will
occur upon detection of a start condition.
• The wakeup function is useful only when the MCU remains in stop/watch mode. (In PLL stop
mode, for example, the time from wakeup to the start of communication becomes longer than
in stop/watch mode as the PLL oscillation stabilization wait time is required in addition to the
oscillation stabilization wait time.)
Table 22.5-1 I
2
C Bus Control Register 0 (IBCR00) (2 / 2)
Bit name
Function
Summary of Contents for F2 MC-8FX Family
Page 2: ......
Page 4: ......
Page 34: ...20 CHAPTER 1 DESCRIPTION ...
Page 38: ...24 CHAPTER 2 HANDLING DEVICES ...
Page 39: ...25 CHAPTER 3 MEMORY SPACE This chapter describes memory space 3 1 Memory Space 3 2 Memory Map ...
Page 56: ...42 CHAPTER 5 CPU ...
Page 73: ...59 CHAPTER 6 CLOCK CONTROLLER ...
Page 96: ...82 CHAPTER 6 CLOCK CONTROLLER ...
Page 104: ...90 CHAPTER 7 RESET ...
Page 105: ...91 CHAPTER 8 INTERRUPTS This chapter explains the interrupts 8 1 Interrupts ...
Page 174: ...160 CHAPTER 10 TIMEBASE TIMER ...
Page 184: ...170 CHAPTER 10 TIMEBASE TIMER ...
Page 218: ...204 CHAPTER 13 WATCH PRESCALER ...
Page 257: ...243 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 261: ...247 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 288: ...274 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 301: ...287 CHAPTER 17 16 BIT PPG TIMER ...
Page 316: ...302 CHAPTER 17 16 BIT PPG TIMER ...
Page 382: ...368 CHAPTER 21 UART SIO DEDICATED BAUD RATE GENERATOR ...
Page 390: ...376 CHAPTER 22 I2C ...
Page 395: ...381 CHAPTER 22 I2C ...
Page 399: ...385 CHAPTER 22 I2C ...
Page 430: ...416 CHAPTER 23 10 BIT A D CONVERTER ...
Page 476: ...462 CHAPTER 24 LCD CONTROLLER ...
Page 482: ...468 CHAPTER 25 LOW VOLTAGE DETECTION RESET CIRCUIT ...
Page 494: ...480 CHAPTER 26 CLOCK SUPERVISOR ...
Page 507: ...493 CHAPTER 27 REAL TIME CLOCK ...
Page 523: ...509 CHAPTER 27 REAL TIME CLOCK ...
Page 532: ...518 CHAPTER 27 REAL TIME CLOCK ...
Page 536: ...522 CHAPTER 28 256 KBIT FLASH MEMORY ...
Page 554: ...540 CHAPTER 28 256 KBIT FLASH MEMORY ...
Page 564: ...550 CHAPTER 29 EXAMPLE OF SERIAL PROGRAMMING CONNECTION ...
Page 595: ...581 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 596: ...582 INDEX Index ...
Page 597: ...583 INDEX ...
Page 600: ...586 Pin Function Index ...
Page 602: ......