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 936 of 1852
Nov 30, 2020
RX23W Group 32. USB 2.0 Host/Function Module (USBc)
32.3.3.3 BEMP Interrupt
On detecting a BEMP interrupt for the pipe whose PID[1:0] bits are set to 01b (BUF) by software, the USB sets the
corresponding BEMPSTS.PIPEnBEMP flag to 1. If the corresponding bit in the BEMPENB register has been set to 1 by
software, the USB sets the INTSTS0.BEMP flag to 1 and generates a USB interrupt.
The following describes the conditions on which the USB generates an internal BEMP interrupt request.
(1) For the pipe in the transmitting direction:
When the FIFO buffer of the corresponding pipe is empty on completion of transmission (including zero-length packet
transmission).
In single buffer mode, an internal BEMP interrupt request is generated simultaneously with the BRDY interrupt for the
pipe other than DCP. However, the internal BEMP interrupt request is not generated on any of the following conditions.
• When the CPU or DMAC/DTC has already started writing data to the FIFO buffer of the CPU on completion of
transmitting data from one FIFO buffer in double buffer mode.
•
When the buffer is cleared (emptied) by setting the PIPEnCTR.ACLRM or the BCLR bit in the port control register to
1.
• When IN transfer (zero-length packet transmission) is performed during the control transfer status stage while the
function controller is selected.
(2) For the pipe in the receiving direction:
When the successfully-received data packet size exceeds the specified maximum packet size.
In this case, the USB generates a BEMP interrupt request, sets the corresponding BEMPSTS.PIPEnBEMP flag to 1,
discards the received data, and modifies the setting of the PID[1:0] bits of the corresponding pipe to 11b (STALL).
Here, the USB returns no response when used as the host controller, and returns STALL response when used as the
function controller.
However, the internal BEMP interrupt request is not generated on any of the following conditions.
• When a CRC error or a bit stuffing error is detected in the received data.
• When a setup transaction is being performed,
Writing 0 to the BEMPSTS.PIPEnBEMP flag clears the status.
Writing 1 to the BEMPSTS.PIPEnBEMP flag has no effect.
Figure 32.10 shows the timing of BEMP interrupt generation when the function controller is selected.
Figure 32.10 Timing of BEMP Interrupt Generation (When Function Controller is Selected)
(1) Example of data transmission
(2) Example of data reception
IN Token Packet
OUT Token Packet
ACK HandshakeData Packet
STALL Handshake
Data Packet (Maximum
Packet size over)
Ready for transmission
Ready for write access
(there is no data to be
transmitted)
Note 1. The handshake is not used in isochronous transfers.
USB bus
FIFO buffer status
BEMP interrupt
(BEMPSTS.PIPEnBEMP flag)
*1
Packet transmitted by host device Packet transmitted by function device
USB bus
BEMP interrupt
(BEMPSTS.PIPEnBEMP flag)
A BEMP interrupt is generated
A BEMP interrupt is generated