How-To Guide
Table Of Contents
- 29. Low-Power Timer (LPT)
- 29.1 Overview
- 29.2 Register Descriptions
- 29.2.1 Low-Power Timer Control Register 1 (LPTCR1)
- 29.2.2 Low-Power Timer Control Register 2 (LPTCR2)
- 29.2.3 Low-Power Timer Control Register 3 (LPTCR3)
- 29.2.4 Low-Power Timer Period Setting Register (LPTPRD)
- 29.2.5 Low-Power Timer Compare Register 0 (LPCMR0)
- 29.2.6 Low-Power Timer Standby Wakeup Enable Register (LPWUCR)
- 29.3 Operation
- 29.4 Wakeup from Software Standby Mode by an Interrupt through the Event Link Controller (ELC)
- 29.5 Usage Notes
- 30. Watchdog Timer (WDTA)
- 30.1 Overview
- 30.2 Register Descriptions
- 30.3 Operation
- 31. Independent Watchdog Timer (IWDTa)
- 31.1 Overview
- 31.2 Register Descriptions
- 31.3 Operation
- 31.3.1 Count Operation in Each Start Mode
- 31.3.2 Control over Writing to the IWDTCR, IWDTRCR, and IWDTCSTPR Registers
- 31.3.3 Refresh Operation
- 31.3.4 Status Flags
- 31.3.5 Reset Output
- 31.3.6 Interrupt Sources
- 31.3.7 Reading the Counter Value
- 31.3.8 Correspondence between Option Function Select Register 0 (OFS0) and IWDT Registers
- 31.4 Link Operation by ELC
- 31.5 Usage Notes
- 32. USB 2.0 Host/Function Module (USBc)
- 32.1 Overview
- 32.2 Register Descriptions
- 32.2.1 System Configuration Control Register (SYSCFG)
- 32.2.2 System Configuration Status Register 0 (SYSSTS0)
- 32.2.3 Device State Control Register 0 (DVSTCTR0)
- 32.2.4 CFIFO Port Register (CFIFO), D0FIFO Port Register (D0FIFO), D1FIFO Port Register (D1FIFO)
- 32.2.5 CFIFO Port Select Register (CFIFOSEL), D0FIFO Port Select Register (D0FIFOSEL), D1FIFO Port Select Register (D1FIFOSEL)
- 32.2.6 CFIFO Port Control Register (CFIFOCTR), D0FIFO Port Control Register (D0FIFOCTR), D1FIFO Port Control Register (D1FIFOCTR)
- 32.2.7 Interrupt Enable Register 0 (INTENB0)
- 32.2.8 Interrupt Enable Register 1 (INTENB1)
- 32.2.9 BRDY Interrupt Enable Register (BRDYENB)
- 32.2.10 NRDY Interrupt Enable Register (NRDYENB)
- 32.2.11 BEMP Interrupt Enable Register (BEMPENB)
- 32.2.12 SOF Output Configuration Register (SOFCFG)
- 32.2.13 Interrupt Status Register 0 (INTSTS0)
- 32.2.14 Interrupt Status Register 1 (INTSTS1)
- 32.2.15 BRDY Interrupt Status Register (BRDYSTS)
- 32.2.16 NRDY Interrupt Status Register (NRDYSTS)
- 32.2.17 BEMP Interrupt Status Register (BEMPSTS)
- 32.2.18 Frame Number Register (FRMNUM)
- 32.2.19 USB Request Type Register (USBREQ)
- 32.2.20 USB Request Value Register (USBVAL)
- 32.2.21 USB Request Index Register (USBINDX)
- 32.2.22 USB Request Length Register (USBLENG)
- 32.2.23 DCP Configuration Register (DCPCFG)
- 32.2.24 DCP Maximum Packet Size Register (DCPMAXP)
- 32.2.25 DCP Control Register (DCPCTR)
- 32.2.26 Pipe Window Select Register (PIPESEL)
- 32.2.27 Pipe Configuration Register (PIPECFG)
- 32.2.28 Pipe Maximum Packet Size Register (PIPEMAXP)
- 32.2.29 Pipe Cycle Control Register (PIPEPERI)
- 32.2.30 Pipe n Control Registers (PIPEnCTR) (n = 1 to 9)
- 32.2.31 Pipe n Transaction Counter Enable Register (PIPEnTRE) (n = 1 to 5)
- 32.2.32 Pipe n Transaction Counter Register (PIPEnTRN) (n = 1 to 5)
- 32.2.33 Device Address n Configuration Register (DEVADDn) (n = 0 to 5)
- 32.2.34 USB Module Control Register (USBMC)
- 32.2.35 BC Control Register 0 (USBBCCTRL0)
- 32.3 Operation
- 32.3.1 System Control
- 32.3.2 Interrupt Sources
- 32.3.3 Interrupt Descriptions
- 32.3.3.1 BRDY Interrupt
- 32.3.3.2 NRDY Interrupt
- 32.3.3.3 BEMP Interrupt
- 32.3.3.4 Device State Transition Interrupt
- 32.3.3.5 Control Transfer Stage Transition Interrupt
- 32.3.3.6 Frame Update Interrupt
- 32.3.3.7 VBUS Interrupt
- 32.3.3.8 Resume Interrupt
- 32.3.3.9 OVRCR Interrupt
- 32.3.3.10 BCHG Interrupt
- 32.3.3.11 DTCH Interrupt
- 32.3.3.12 SACK Interrupt
- 32.3.3.13 SIGN Interrupt
- 32.3.3.14 ATTCH Interrupt
- 32.3.3.15 EOFERR Interrupt
- 32.3.3.16 Portable Device Detection Interrupt
- 32.3.4 Pipe Control
- 32.3.4.1 Pipe Control Register Switching Procedures
- 32.3.4.2 Transfer Types
- 32.3.4.3 Endpoint Number
- 32.3.4.4 Maximum Packet Size Setting
- 32.3.4.5 Transaction Counter (For Pipes 1 to 5 in Reading Direction)
- 32.3.4.6 Response PID
- 32.3.4.7 Data PID Sequence Bit
- 32.3.4.8 Response PID = NAK Function
- 32.3.4.9 Auto Response Mode
- 32.3.4.10 OUT-NAK Mode
- 32.3.4.11 Null Auto Response Mode
- 32.3.5 FIFO Buffer Memory
- 32.3.6 Control Transfers Using DCP
- 32.3.7 Bulk Transfers (Pipes 1 to 5)
- 32.3.8 Interrupt Transfers (Pipes 6 to 9)
- 32.3.9 Isochronous Transfers (Pipes 1 and 2)
- 32.3.10 SOF Interpolation Function
- 32.3.11 Pipe Schedule
- 32.4 Usage Notes
- 32.5 Battery Charging Detection Processing
- 33. Serial Communications Interface (SCIg, SCIh)
- 33.1 Overview
- 33.2 Register Descriptions
- 33.2.1 Receive Shift Register (RSR)
- 33.2.2 Receive Data Register (RDR)
- 33.2.3 Receive Data Register H, L, HL (RDRH, RDRL, RDRHL)
- 33.2.4 Transmit Data Register (TDR)
- 33.2.5 Transmit Data Register H, L, HL (TDRH, TDRL, TDRHL)
- 33.2.6 Transmit Shift Register (TSR)
- 33.2.7 Serial Mode Register (SMR)
- 33.2.8 Serial Control Register (SCR)
- 33.2.9 Serial Status Register (SSR)
- 33.2.10 Smart Card Mode Register (SCMR)
- 33.2.11 Bit Rate Register (BRR)
R01UH0823EJ0110 Rev.1.10 Page 876 of 1852
Nov 30, 2020
RX23W Group 32. USB 2.0 Host/Function Module (USBc)
FRDY Flag (FIFO Port Ready Flag)
The FRDY flag indicates whether the FIFO port can be accessed by the CPU or DMAC/DTC.
In the following cases, the USB sets the FRDY flag to 1 but data cannot be read via the FIFO port because there is no
data to be read. In these cases, set the BCLR bit to 1 to clear the FIFO buffer, and enable transmission and reception of
the next data.
• A zero-length packet is received when the FIFO buffer assigned to the selected pipe is empty.
• A short packet is received and the data is completely read while the PIPECFG.BFRE bit = 1.
BCLR Bit (CPU Buffer Clear)
The BCLR bit should be set to 1 to clear the FIFO buffer on the CPU side for the selected pipe.
When double buffer mode is set for the FIFO buffer assigned to the selected pipe, the USB clears only the FIFO buffer on
the CPU side even when both planes are read-enabled.
When the selected pipe is the DCP, setting the BCLR bit to 1 allows the USB to clear the FIFO buffer regardless of
whether the FIFO buffer is on the CPU side or SIE side. To clear the buffer on the SIE side, set the DCPCTR.PID[1:0]
bits for the DCP to 00b (NAK) before setting the BCLR bit to 1.
When the selected pipe is in the transmitting direction, if 1 is written to the BVAL bit and the BCLR bit simultaneously,
the USB clears the data that has been written before it, enabling transmission of a zero-length packet.
When the selected pipe is not the DCP, writing 1 to the BCLR bit should be done while the FRDY flag in the FIFO port
control register is 1 (set by the USB).
BVAL Bit (Buffer Memory Valid)
The BVAL bit should be set to 1 when data has been completely written to the FIFO buffer on the CPU side for the pipe
selected using the CURPIPE[3:0] bits (selected pipe).
When the selected pipe is in the transmitting direction, set the BVAL bit to 1 in the following cases. Then, the USB
switches the FIFO buffer from the CPU side to the SIE side, thus enabling transmission.
• To transmit a short packet, set the BVAL bit to 1 after data has been written.
• To transmit a zero-length packet, set the BVAL bit to 1 before data is written to the FIFO buffer.
When data of the maximum packet size has been written for the pipe in continuous transfer mode, the USB sets the
BVAL bit to 1 and switches the FIFO buffer from the CPU side to the SIE side, thus enabling transmission.
Writing 1 to the BVAL bit should be done while the FRDY flag is 1 (set by the USB).
When the selected pipe is in the receiving direction, do not set the BVAL bit to 1.