ST7PLITEU09M3TR View Datasheet(PDF) - STMicroelectronics

Part Name

Description

Manufacturer

ST7PLITEU09M3TR

8-bit MCU with single voltage Flash memory, ADC, timers

STMicroelectronics 

ST7LITEU05 ST7LITEU09

POWER SAVING MODES (Cont’d)

9.5.1 Register Description

AWUFH CONTROL/STATUS REGISTER

(AWUCSR)

Read / Write

Reset Value: 0000 0000 (00h)

7

0

AWUFH PRESCALER REGISTER (AWUPR)

Read / Write

Reset Value: 1111 1111 (FFh)

7

0

AWU AWU AWU AWU AWU AWU AWU AWU

PR7 PR6 PR5 PR4 PR3 PR2 PR1 PR0

0

0

0

0

Bits 7:3 = Reserved.

0

AWU AWU AWU

F M EN

Bit 2= AWUF Auto Wake Up Flag

This bit is set by hardware when the AWU module

generates an interrupt and cleared by software on

reading AWUCSR. Writing to this bit does not

change its value.

0: No AWU interrupt occurred

1: AWU interrupt occurred

Bit 1= AWUM Auto Wake Up Measurement

This bit enables the AWU RC oscillator and con-

nects its output to the input capture of the 8-bit Lite

timer. This allows the timer to be used to measure

the AWU RC oscillator dispersion and then com-

pensate this dispersion by providing the right value

in the AWUPRE register.

0: Measurement disabled

1: Measurement enabled

Bit 0 = AWUEN Auto Wake Up From Halt Enabled

This bit enables the Auto Wake Up From Halt fea-

ture: once HALT mode is entered, the AWUFH

wakes up the microcontroller after a time delay de-

pendent on the AWU prescaler value. It is set and

cleared by software.

0: AWUFH (Auto Wake Up From Halt) mode disa-

bled

1: AWUFH (Auto Wake Up From Halt) mode ena-

bled

Note: whatever the clock source, this bit should be

set to enable the AWUFH mode once the HALT in-

struction has been executed.

Bits 7:0= AWUPR[7:0] Auto Wake Up Prescaler

These 8 bits define the AWUPR Dividing factor (as

explained below:

AWUPR[7:0]

00h

01h

...

FEh

FFh

Dividing factor

Forbidden

1

...

254

255

In AWU mode, the period that the MCU stays in

Halt Mode (tAWU in Figure 30 on page 44) is de-

fined by

tAWU

=

64 × AWUPR × ------------1-------------

fAWURC

+ tRCSTRT

This prescaler register can be programmed to

modify the time that the MCU stays in Halt mode

before waking up automatically.

Note: If 00h is written to AWUPR, depending on

the product, an interrupt is generated immediately

after a HALT instruction, or the AWUPR remains

unchanged.

Table 14. AWU Register Map and Reset Values

Address

(Hex.)

0049h

004Ah

Register

Label

AWUPR

Reset Value

AWUCSR

Reset Value

7

AWUPR7

1

0

6

AWUPR6

1

0

5

AWUPR5

1

0

4

AWUPR4

1

0

3

AWUPR3

1

0

2

AWUPR2

1

AWUF

1

AWUPR1

1

AWUM

0

AWUPR0

1

AWUEN

46/115

1

Share Link: