Freescale Semiconductor Demonstration Board for Freescale MC9S12XHY256 Microcontroller DEMO9S12XHY256 DEMO9S12XHY256 用户手册
产品代码
DEMO9S12XHY256
Port Integration Module (S12XHYPIMV1)
MC9S12XHY-Family Reference Manual, Rev. 1.04
86
Freescale Semiconductor
2.3.3
Port A Data Register (PORTA)
Address 0x0000 (PRR)
Access: User read/write
1
1
Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
Write: Anytime
7
6
5
4
3
2
1
0
R
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
W
—
—
—
—
API_EXTCLK
—
XIRQ
IRQ
Altern.
Function
FP36
FP35
FP34
FP33
FP32
FP31
FP30
FP29
Reset
0
0
0
0
0
0
0
0
Figure 2-1. Port A Data Register (PORTA)
Table 2-4. PORTA Register Field Descriptions
Field
Description
7-4,2
PA
Port A general purpose input/output data—Data Register, LCD segment driver output
The associated pin can be used as general purpose I/O when not used as alternative function is not enabled. In
general purpose output mode the register bit value is driven to the pin. If the associated data direction bit is set to 1,
a read returns the value of the port register bit, otherwise the buffered pin input state is read.
• The LCD segment driver output takes precedence over the general purpose I/O function if the related LCD
The associated pin can be used as general purpose I/O when not used as alternative function is not enabled. In
general purpose output mode the register bit value is driven to the pin. If the associated data direction bit is set to 1,
a read returns the value of the port register bit, otherwise the buffered pin input state is read.
• The LCD segment driver output takes precedence over the general purpose I/O function if the related LCD
segment is enabled.
3
PA
Port A general purpose input/output data—Data Register, LCD segment driver output, API_EXTCLK
The associated pin can be used as general purpose I/O when not used as alternative function. In general purpose
output mode the register bit value is driven to the pin. If the associated data direction bit is set to 1, a read returns
the value of the port register bit, otherwise the buffered pin input state is read.
• The LCD segment driver output takes precedence over the API_EXTCLK and general purpose I/O function if the
The associated pin can be used as general purpose I/O when not used as alternative function. In general purpose
output mode the register bit value is driven to the pin. If the associated data direction bit is set to 1, a read returns
the value of the port register bit, otherwise the buffered pin input state is read.
• The LCD segment driver output takes precedence over the API_EXTCLK and general purpose I/O function if the
related LCD segment is enabled.
• The API_EXTCLK takes precedence over the general purpose I/O function if the API_EXTCLK function is enabled
1
PA
Port A general purpose input/output data—Data Register, LCD segment driver output, XIRQ
The associated pin can be used as general purpose I/O when not used as alternative function. In general purpose
output mode the register bit value is driven to the pin. If the associated data direction bit is set to 1, a read returns
the value of the port register bit, otherwise the buffered pin input state is read.
• The LCD segment driver output takes precedence over the XIRQ and general purpose I/O function if the related
The associated pin can be used as general purpose I/O when not used as alternative function. In general purpose
output mode the register bit value is driven to the pin. If the associated data direction bit is set to 1, a read returns
the value of the port register bit, otherwise the buffered pin input state is read.
• The LCD segment driver output takes precedence over the XIRQ and general purpose I/O function if the related
LCD segment is enabled.
• The XIRQ takes precedence over the general purpose I/O function if the XIRQ function is enabled
0
PA
Port A general purpose input/output data—Data Register, LCD segment driver output, IRQ
The associated pin can be used as general purpose I/O when not used as alternative function. In general purpose
output mode the register bit value is driven to the pin. If the associated data direction bit is set to 1, a read returns
the value of the port register bit, otherwise the buffered pin input state is read.
• The LCD segment driver output takes precedence over the IRQ and general purpose I/O function if the related
The associated pin can be used as general purpose I/O when not used as alternative function. In general purpose
output mode the register bit value is driven to the pin. If the associated data direction bit is set to 1, a read returns
the value of the port register bit, otherwise the buffered pin input state is read.
• The LCD segment driver output takes precedence over the IRQ and general purpose I/O function if the related
LCD segment is enabled.
• The IRQ takes precedence over the general purpose I/O function if the IRQ function is enabled