Toshiba TLCS-900/H1 Series Manual page 104

3.5.16 Port L (PL0 to PL7)
PL0 to PL3 are 4-bit output ports. Resetting sets the output latch PL to "0", and PL0 to
PL3 pins output "0".
PL4 to PL7 are 4-bit general-purpose I/O ports. Each bit can be set individually for input
or output using the control register PLCR. Resetting resets the control register PLCR to "0"
and sets PL4 to PL7 to input ports. In addition to functioning as a general-purpose I/O port,
port L can also function as a data bus for an LCD controller (LD0 to LD7). The above
settings are made using the function register PLFC.
Reset
LD0 to LD3
Direction control
Function control
LD4 to LD7
Function control
PLFC write
R
Output latch
A
PL write
B
PL read
Figure 3.5.43 Register for Port L0 to L3
Reset
PLCR write
PLFC write
S
A
Output latch
Selector
B
PL write
Selector
PL read
Figure 3.5.44 Register for Port L4 to L7
92CH21-102
S
Selector
S
S
B
A
TMP92CH21
PL0 to PL3 (LD0 to LD3)
PL4 to PL7 (LD4 to LD7)
2009-06-19