ST7LITE0XY0 datasheet(43/124 Pages) STMICROELECTRONICS

43 / 124 page

ST7LITE0xY0, ST7LITESxY0

43/124

– reset the interrupt mask with the RIM instruc-

tion (in cases where a pin level change could

occur)

Output Modes

The output configuration is selected by setting the

corresponding DDR register bit. In this case, writ-

ing the DR register applies this digital value to the

I/O pin through the latch. Then reading the DR reg-

ister returns the previously stored value.

Two different output modes can be selected by

software through the OR register: Output push-pull

and open-drain.

DR register value and output pin status:

Note: When switching from input to output mode,

the DR register has to be written first to drive the

correct level on the pin as soon as the port is con-

figured as an output.

10.2.2 Alternate Functions

When an on-chip peripheral is configured to use a

pin, the alternate function is automatically select-

ed. This alternate function takes priority over the

standard I/O programming under the following

conditions:

– When the signal is coming from an on-chip pe-

ripheral, the I/O pin is automatically configured in

output mode (push-pull or open drain according

to the peripheral).

– When the signal is going to an on-chip peripher-

al, the I/O pin must be configured in floating input

mode. In this case, the pin state is also digitally

readable by addressing the DR register.

Notes:

– Input pull-up configuration can cause unexpect-

ed value at the input of the alternate peripheral

input.

– When an on-chip peripheral use a pin as input

and output, this pin has to be configured in input

floating mode.

Push-pull

Open-drain

0VSS

Vss

1VDD

Floating

ST7LITE0XY0 数据表(PDF) 43 Page - STMicroelectronics

ST7LITE0XY0 数据表(HTML) 43 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载