R01UH0823EJ0100 Rev.1.00
Page 1420 of 1823
Jul 31, 2019
RX23W Group
40. SD Host Interface (SDHIa)
40.
SD Host Interface (SDHIa)
This MCU incorporates an SD host interface (SDHI) which is compliant with the SD Specifications. When developing
host devices that are compliant with the SD Specifications, the user must enter into the SD Host/Ancillary Product
License Agreement (SD HALA).
40.1
Overview
lists the SDHI specifications.
shows a block diagram of the SDHI.
Figure 40.1
Block Diagram of the SDHI
lists the pin configuration of the SDHI.
Table 40.1
SDHI Specifications
Item
Description
SD bus interface
Compatible with SD memory card and SDIO card (
NOT
compatible with the SPI bus interface,
embedded SDIO shared bus, 8-bit SD bus, or SDIO suspend/resume functions)
Transfer bus mode selectable from 4-bit wide bus mode or 1-bit default bus mode
Compatible with SD, SDHC, and SDXC formats
Transfer modes
Supports default speed mode
SDHI clock
The SDHI clock is generated by dividing peripheral module clock B (PCLKB) by
n
, where
n
= 1, 2, 4, 8,
16, 32, 64, 128, 256, or 512
Error check functions
CRC7 (command/response)
CRC16 (transfer data)
Interrupt sources
Card access interrupt (CACI)
SDIO access interrupt (SDACI)
Card detection interrupt (CDETI)
SD buffer access interrupt (SBFAI)
DMA transfer sources
DMAC and DTC triggerable by the SBFAI interrupt
SD buffer is read and write accessible using the DMAC and DTC
Other functions
Card detection
Write protection
Table 40.2
Pin Configuration of the SDHI
Pin Name
I/O
Description
SDHI_CLK
Output
SDHI clock
SDHI_CMD
I/O
Command output, response input
SDHI_D0
I/O
Data 0 (DAT0)
SDHI_D1
I/O
Data 1 (DAT1), SDIO access interrupt
SDHI_D2
I/O
Data 2 (DAT2), read wait
SDHI_D3
I/O
Data 3 (DAT3), SD card detection
SDHI_CD
Input
SD card detection
SDHI_WP
Input
SD card write protection
SD
card
SD card
interface
SD
in
ter
fa
ce
Host
inte
rfa
ce
SD buffer
(512 bytes × 2)
DMA interface
Interrupt request
PCLKB
In
te
rn
al
p
er
ip
he
ra
l b
us