MC908QT4MPE datasheet(90/184 Pages) FREESCALE

90 / 184 page

Oscillator Module (OSC)

MC68HC908QY/QT Family Data Sheet, Rev. 5

Freescale Semiconductor

Figure 11-1. Block Diagram Highlighting OSC Block and Pins

11.3.1 Internal Oscillator

The internal oscillator circuit is designed for use with no external components to provide a clock source

with tolerance less than ±25% untrimmed.An 8-bit trimming register allows adjustment to a tolerance of

less than ±5%.

The internal oscillator will generate a clock of 12.8 MHz typical (INTCLK) resulting in a bus speed (internal

clock

÷ 4) of 3.2 MHz. 3.2 MHz came from the maximum bus speed guaranteed at 3 V which is 4

MHz.Since the internal oscillator will have a ±25% tolerance (pre-trim), then the +25% case should not

allow a frequency higher than 4 MHz:

3.2 MHz + 25% = 4 MHz

Figure 11-3 shows how BUSCLKX4 is derived from INTCLK and, like the RC oscillator, OSC2 can output

BUSCLKX4 by setting OSC2EN in PTAPUE register. See Chapter 12 Input/Output Ports (PORTS)

PTA0/AD0/TCH0/KBI0

PTA1/AD1/TCH1/KBI1

PTA2/IRQ/KBI2/TCLK

PTA3/RST/KBI3

PTA4/OSC2/AD2/KBI4

PTA5/OSC1/AD3/KBI5

KEYBOARD INTERRUPT

MODULE

CLOCK

GENERATOR

(OSCILLATOR)

SYSTEM INTEGRATION

MODULE

SINGLE INTERRUPT

MODULE

BREAK

MODULE

POWER-ON RESET

MODULE

16-BIT TIMER

MODULE

COP

MODULE

MONITOR ROM

PTB0

M68HC08 CPU

PTB1

PTB2

PTB3

PTB4

PTB5

PTB6

PTB7

8-BIT ADC

128 BYTES RAM

MC68HC908QY4 AND MC68HC908QT4

4096 BYTES

MC68HC908QY2, MC68HC908QY1,

MC68HC908QT2, AND MC68HC908QT1:

1536 BYTES

USER FLASH

POWER SUPPLY

VDD

VSS

RST, IRQ: Pins have internal (about 30K Ohms) pull up

PTA[0:5]: High current sink and source capability

PTA[0:5]: Pins have programmable keyboard interrupt and pull up

PTB[0:7]: Not available on 8-pin devices – MC68HC908QT1, MC68HC908QT2, and MC68HC908QT4 (see note in

12.1 Introduction)

ADC: Not available on the MC68HC908QY1 and MC68HC908QT1

MC908QT4MPE bảng dữ liệu(PDF) 90 Page - Freescale Semiconductor, Inc

MC908QT4MPE bảng dữ liệu(HTML) 90 Page - Freescale Semiconductor, Inc

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

bảng dữ liệu tải về

Link URL