ST72361 datasheet(59/224 Pages) STMICROELECTRONICS

59 / 224 page

ST72361

59/224

ON-CHIP PERIPHERALS (Cont’d)

10.2 MAIN CLOCK CONTROLLER WITH REAL TIME CLOCK MCC/RTC

The Main Clock Controller consists of three differ-

ent functions:

■

a programmable CPU clock prescaler

■

a clock-out signal to supply external devices

■

a real time clock timer with interrupt capability

Each function can be used independently and si-

multaneously.

10.2.1 Programmable CPU Clock Prescaler

The programmable CPU clock prescaler supplies

the clock for the ST7 CPU and its internal periph-

erals. It manages SLOW power saving mode (See

Section 8.2 "SLOW MODE" for more details).

The prescaler selects the fCPU main clock frequen-

cy and is controlled by three bits in the MCCSR

10.2.2 Clock-out Capability

The clock-out capability is an alternate function of

an I/O port pin that outputs a fOSC2 clock to drive

external devices. It is controlled by the MCO bit in

the MCCSR register.

10.2.3 Real Time Clock Timer (RTC)

The counter of the real time clock timer allows an

interrupt to be generated based on an accurate

real time clock. Four different time bases depend-

ing directly on fOSC2 are available. The whole

functionality is controlled by 4 bits of the MCCSR

When the RTC interrupt is enabled (OIE bit set),

the ST7 enters ACTIVE HALT mode when the

HALT instruction is executed. See Section 8.5

"ACTIVE HALT MODE" for more details.

Figure 39. Main Clock Controller (MCC/RTC) Block Diagram

DIV 2, 4, 8, 16

MCC/RTC INTERRUPT

SMS

CP1 CP0

TB1

TB0

OIE

OIF

CPU CLOCK

MCCSR

RTC

COUNTER

TO CPU AND

PERIPHERALS

fOSC2

fCPU

MCO

WATCHDOG

TIMER

ST72361 데이터시트(PDF) 59 Page - STMicroelectronics

ST72361 데이터시트(HTML) 59 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

데이터시트 다운로드

링크 URL