HD6417641 RENESAS [Renesas Technology Corp], HD6417641 Datasheet - Page 891

• Manufacturer Part Number: HD6417641
• Manufacturer: RENESAS [Renesas Technology Corp]

22.2
22.2.1
All the I/O buffers except PTG10, PTG9, and PTG 7 to PTG 0 (IIC2 and analog pins) listed in
table 22.1 have weak keepers that consist of two inverters to keep the status of the pin. Figure 22.1
shows the internal block diagram of the I/O buffer.
22.2.2
PTG10 and PTG9 are multiplexed with the IIC2 (SDA, SCL) pins and consist of the normal I/O
buffer and the I/O buffer with an open drain output. Setting the port G control register (PGCR) to
port input or port output enables the normal I/O buffer. Setting the PGCR to other function (IIC2)
enables the I/O buffer with an open drain output.
Figure 22.2 shows the internal block diagram of the I/O buffer with an open drain output.
I/O Buffer Internal Block Diagram
I/O Buffer with Weak Keeper
I/O Buffer with Open Drain Output
Figure 22.1 Internal Block Diagram of I/O Buffer with Weak Keeper
Output enalbe
Output data
Input data
I/O buffer
Weak keeper
Rev. 4.00 Sep. 14, 2005 Page 841 of 982
Section 22 Pin Function Controller (PFC)
REJ09B0023-0400