SH7730 Datasheet, PDF (901/1188 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7780 Series

Section 25 SIM Card Module (SIM)
(3) Temporary High-Output Function
Setting the HOEN bit in SCSCMR to 1 enables the smart card interface to use the temporary high-
output function after transmitting one frame of data. If the temporary high-output function is
disabled, when the data line is driven to high impedance by negating the tristate buffer after
transmission of one frame, pulling up the data line to high level takes time. When the temporary
high-output function is enabled, high-level is forcibly output for one system clock cycle before
negating the tristate buffer after transmission of one frame, thus reducing the time to fix the data
line to high level. A timechart is shown in figure 25.10.
High-output function off
LSI internal data
LSI internal output enable
Transmit data (TXD)
High-output function on
LSI internal data
LSI internal output enable
Transmit data (TXD)
Data
Data
Data
Data
Figure 25.10 High-Output Function Timechart
Rev. 1.00 Sep. 19, 2007 Page 853 of 1136
REJ09B0359-0100