Datasheet

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ST7LITE20F2 ST7LITE25F2 ST7LITE29F2 Power saving modes

169

AWUF prescaler register list (AWUPR)

Read / Write

Reset value: 1111 1111 (FFh)

• Bits 7:0= AWUPR[7:0] Auto-wakeup prescaler

These 8 bits define the AWUPR dividing factor (as explained in Table 19: AWU

prescaler below):

In AWU mode, the period that the MCU stays in HALT mode (t

AWU

in Figure 29: AWUF halt

timing diagram) is defined by:

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.

7 0

AWUPR7 AWUPR6 AWUPR5 AWUPR4 AWUPR3 AWUPR2 AWUPR1 AWUPR0

Table 19. AWU prescaler

AWUPR[7:0] Dividing factor

00h Forbidden

01h 1

−−

FEh 254

FFh 255

AWU

64 AWUPR×

AWURC

-------------------- t

RCSTRT

+×=

Table 20. AWU register map and reset values

Addres

(Hex.)

label

76543210

0049h

AWUPR

Reset

value

AWUPR

004Ah

AWUCSR

Reset

value

0 0 0 0 0 AWUF AWUM AWUEN