TMP88CU74F datasheet(23/132 Pages) TOSHIBA

23 / 132 page

TMP88CU74

2003-02-17

88CU74-23

Switching from SLOW mode to NORMAL2 mode

First, set XEN (bit 7 in SYSCR2) to turn on the high-frequency oscillation.

When time for stabilization (warm-up) has been taken by the timer/counter 2

(TC2), clear SYSCK (bit 5 in SYSCR2) to switch the main system clock to the

high-frequency clock.

Note 1: After SYSCK is cleared to "0", executing the instructions is continued by the

low-frequency clock for the period synchronized with low-frequency and

high-frequency clocks.

Note 2: SLOW mode can also be released by inputting low level on the RESET pin, which

immediately performs the reset operation. After reset, the TMP88CU74 is placed in

NORMAL1 mode.

Example: Switching from SLOW mode to NORMAL2 mode

(fc = 12.5 MHz, warming-up time is 5.8 ms).

SET

(SYSCR2). 7

;

XEN

← 1 (turns on high-frequency

oscillation)

(TC2CR), 10H

;

Sets TC2 mode (timer mode, source

clock: fc)

(TREG2

+ 1), 0F8H

;

Sets the warming-up time (according to

frequency and Xtal characteristics)

SET

(EIRH). EF14

;

Enables INTTC2

(TC2CR), 30H

;

Starts TC2

PINTTC2:

(TC2CR), 10H

;

Stops TC2

CLR

(SYSCR2). 5

;

SYSCK

← 0 (switches the main system

clock to the high-frequency clock)

RETI

VINTTC2:

PINTTC2

;

INTTC2 vector table

High-frequency clock

Low-frequency clcok

Main system clock

SYSCK

2007-10-19

TMP88CU74F Datasheet(PDF) 23 Page - Toshiba Semiconductor

TMP88CU74F Datasheet(HTML) 23 Page - Toshiba Semiconductor

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

Datasheet Descarga

Enlace URL