tmp89fm42 TOSHIBA Semiconductor CORPORATION, tmp89fm42 Datasheet - Page 298

• Manufacturer Part Number: tmp89fm42
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

18.5 Data Transfer of I2C Bus
18. Serial Bus Interface (SBI)
RA001
Example :Generate a restart
SCL (Bus)
SCL0 pin
SDA0 pin
SBI0SR2<LRB>
SBI0SR2<BB>
SBI0CR2<PIN>
low level by other devices.
condition and slave address generation".
mode I
restarting to confirm that a bus is free until the time to generate a start condition.
Check SBI0SR2<LRB> until it becomes "1" to check that the SCL line on the bus is not pulled down to the
After confirming that the bus stays in a free state, generate a start condition in the procedure "18.5.2 Start
In order to meet the setup time at a restart, take at least 4.7Ps of waiting time by the software in the standard
Note:When the master is in the receiver mode, it is necessary to stop the data transmission from the slave device
CHK_BB:
CHK_LRB:
before the STOP condition is generated. To stop the transmission, the master device make the slave device
receiving a negative acknowledge. Therefore, SBI0SR2<LRB> is "1" before generating the Restart and it can
not be confirmed that SCL line is not pulled down by other devices. Please confirm the SCL line state by read-
ing the port.
2
C bus standard or at least 0.6Ps of waiting time in the fast mode I
SBI0CR2<TRX>="0"
SBI0CR2<BB>="0"
SBI0CR2<PIN>="1"
SBI0CR2<MST>="0"
LD
TEST
JR
TEST
JR
LD
Figure 18-22 Timing Diagram When Restarting
(SBI0CR2), 0x18
(SBI0SR2).BB
T, CHK_BB
(SBI0SR2).LRB
F, CHK_LRB
.
.
.
(SBI0CR2), 0xf8
Page 284
4.7
0.6
µ
µ
; Sets SBI0CR2<MST>, <TRX> and <BB> to "0" and SBI0CR2<PIN> to
"1"
; Waits until SBI0SR2<BB> becomes "0"
; Waits until SBI0SR2<LRB> becomes "1"
; Wait time process by the software
; Sets SBI0CR2<MST>, <TRX>, <BB> and <PIN> to "1"
s min. in the normal mode or
s min. in the fast mode
SBI0CR2<MST>="1"
SBI0CR2<TRX>="1"
SBI0CR2<BB>="1"
SBI0CR2<PIN>="1"
2
C bus standard from the time of
TMP89FM42
Start condition