h8s-2158 Renesas Electronics Corporation., h8s-2158 Datasheet - Page 253

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

When the RFU is emptied during data transmission, the transmission resume trigger (the
DATAEN bit in OPCR is set) is set once the RFU empty is cancelled (after the necessary data is
written), and data transmission is resumed.
When data reception is started, data is automatically written to the RFU. When the RFU is filled
during data reception, the reception resume trigger (the RD_CONTI bit in OPCR is set) is set once
the RFU full is cancelled (after the necessary data is read from the RFU), and data reception is
resumed.
Hardware (MCIF, RFU)
(reception halted)
Card clock stop
NO
NO
(data transmission to multimedia card)
1-byte data read from RFU
1-byte data transmission
All data transmission
Command transmission
Data transmission
to multimedia card
start instruction?
Data read from
RFU ended?
FIFO empty
NO
NO
ended?
YES
YES
Figure 8.11 Operation Flow of MCIF Transmission
Previous data
read sequence
Empty cancellation
YES
YES
FIFO empty cancellation
waiting fo card clock stop
Data transmission end
(transmission halted)
(Data transmission start)
(Transmission resumption)
NO
Firmware (CPU)
FIFO empty cancellation
resumption instruction
Rev. 3.00 Jan 25, 2006 page 201 of 872
Data transmission
(data write to RFU)
FIFO empty
(data transmission to multimedia card)
YES
Section 8 RAM-FIFO Unit (RFU)
Command transmission
Data transmission
start instruction
transmission command
Command sequence end
sequence ended?
REJ09B0286-0300
Data
YES
NO