Datasheet
V850ES/JG3-H, V850ES/JH3-H CHAPTER 18 3-WIRE VARIABLE-LENGTH SERIAL I/O (CSIF)
R01UH0042EJ0500 Rev.5.00 Page 799 of 1513
Aug 12, 2011
(2) Operation timing
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
SCKFn pin
CFnTSF bit
(1)
(2)
(3)
(4) (5) (6) (7) (8) (9) (11)(10)
SOFn pin
INTCFnT signal
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
(1) Write 07H to the CFnCTL1 register, and select communication type 1, communication clock (fCCLK) =
external clock (SCKFn), and slave mode.
(2) Write 00H to the CFnCTL2 register, and set the transfer data length to 8 bits.
(3) Write C3H to the CFnCTL0 register, and select the transmission mode, MSB first, and continuous
transfer mode at the same time as enabling the operation of the communication clock (f
CCLK).
(4) The CFnSTR.CFnTSF bit is set to 1 by writing the transmit data to the CFnTX register, and the device
waits for a serial clock input.
(5) When a serial clock is input, output the transmit data from the SOFn pin in synchronization with the
serial clock.
(6) When transfer of the transmit data from the CFnTX register to the shift register is completed and
writing to the CFnTX register is enabled, the transmission enable interrupt request signal (INTCFnT) is
generated.
(7) To continue transmission, write the transmit data to the CFnTX register again after the INTCFnT signal
is generated.
(8) When a serial clock is input following completion of the transmission of the transfer data length set with
the CFnCTL2 register, continuous transmission is started.
(9) When transfer of the transmit data from the CFnTX register to the shift register is completed and
writing to the CFnTX register is enabled, the INTCFnT signal is generated. To end continuous
transmission with the current transmission, do not write to the CFnTX register.
(10) When the clock of the transfer data length set with the CFnCTL2 register is input without writing to the
CFnTX register, clear the CFnTSF bit to 0 to end transmission.
(11) To release the transmission enable status, write CFnCTL0.CFnPWR bit = 0 and CFnCTL0.CFnTXE bit
= 0 after checking that the CFnTSF bit = 0.
Caution In continuous transmission mode, the reception completion interrupt request signal
(INTCFnR) is not generated.
Remark n = 0 to 4