h8s-2158 Renesas Electronics Corporation., h8s-2158 Datasheet - Page 692

• Manufacturer Part Number: h8s-2158
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 19 Multimedia Card Interface (MCIF)
19.3.8
CMDSTRT triggers the start of command transmission, representing the start of a command
sequence. The following operations should be completed before the command sequence starts.
The command sequences are controlled by the sequencers in each MCIF side and MMC side.
Normally, these operate synchronously, however, these may temporarily become unsynchronized
when an error occurs or when a command is aborted. Take care to set the CMDOFF bit in OPCR,
to issue the CMD12 command, and to process an error in MMC mode. A new command sequence
should be started after confirming that the command sequences on both the MCIF and MMC sides
have ended.
Rev. 3.00 Jan 25, 2006 page 640 of 872
REJ09B0286-0300
Bit
7 to
1
0
Analysis of prior command response, clearing the command response register write if
necessary
Analysis/transfer of receive data of prior command if necessary
Preparation of transmission data of the next command if necessary
Setting of CMDTYR, RSPTYR, TBCR, and TBNCR
CMDTYR, RSPTYR, TBCR, and TBNCR should not be changed until the command sequence
has ended.
Setting of CMDR0 to CMDR4
CMDR0 to CMDR4 should not be changed until the command sequence has ended (the
CWRE flag in CSTR has been reset, or a command transmission end interrupt has been
generated).
Bit Name
—
START
Command Start Register (CMDSTRT)
Initial Value
All 0
0
R/W
R/(W)
R/W
Description
Reserved
The initial value should not be changed.
Command Sequence Start Bit
Starts command transmission when 1 is written.
This bit is always read as 0.
[Clearing condition]
Automatically cleared when command
transmission starts