446
16.4.2
Port C Data Register (PCDR)
PCDR is an 16-bit read-only register that stores data for port C (writes to bits 15–8 are ignored,
and the read value is always undefined). Bits PC7DR–PC0DR correspond to the PC7/AN7–
PC0/AN0 pins respectively. Any values written to these bits will be ignored and will not affect the
pin status. When the bits are read, the pin status rather than the bit value is read directly. When
analog input of the A/D converter is being sampled, however, every bit is read as 1. Table 16.6
shows port C data register read/write operations (bits 7–0).
PCDR is not initialized by a power-on reset or manual reset, or in standby mode or sleep mode
(bits 15–8 are always undefined; bits 7–0 always reflect the pin status).
Bit:
15
14
13
12
11
10
9
8
Bit name:
—
—
—
—
—
—
—
—
Initial value:
—
—
—
—
—
—
—
—
R/W:
R
R
R
R
R
R
R
R
Bit:
7
6
5
4
3
2
1
0
Bit name:
PC7DR
PC6DR
PC5DR
PC4DR
PC3DR
PC2DR
PC1DR
PC0DR
Initial value:
—
—
—
—
—
—
—
—
R/W:
R
R
R
R
R
R
R
R
Table 16.6
Port C Data Register (PCDR) Read/Write Operations
Pin I/O
Pin Function
Read
Write
Input
General
purpose
Pin status read
Ignored (no effect on pin status)
ANn
Read as 1
Ignored (no effect on pin status)
ANn: Analog input
Содержание HD6417032
Страница 21: ......
Страница 35: ...xiv ...
Страница 85: ...50 ...
Страница 101: ...66 ...
Страница 129: ...94 ...
Страница 135: ...100 ...
Страница 343: ...308 ...
Страница 369: ...334 ...
Страница 383: ...348 ...
Страница 475: ...440 ...
Страница 525: ...490 CK RAS CAS TRp TRc TRcc tRASD1 tRASD2 tCASD3 tCASD2 TRr tCSR Figure 20 18 Self Refresh ...
Страница 578: ...543 CK RAS CAS TRp TRc TRcc tRASD1 tRASD2 tCASD3 tCASD2 TRr tCSR Figure 20 62 Self Refresh ...
Страница 689: ...654 ...