Datasheet

MC68HC908JB8•MC68HC08JB8•MC68HC08JT8 — Rev. 2.3 Technical Data Freescale Semiconductor General Description 31
General Description
MCU Block Diagram
Figure 1-1. MCU Block Diagram
SYSTEM INTEGRATION
MODULE
TIMER INTERFACE
MODULE
LOW VOLTAGE INHIBIT
MODULE
COMPUTER OPERATING PROPERLY
MODULE
ARITHMETIC/LOGIC
UNIT (ALU)
CPU
REGISTERS
M68HC08 CPU
CONTROL AND STATUS REGISTERS — 64 BYTES
USER FLASH MEMORY — 8,192 BYTES
USER RAM — 256 BYTES
MONITOR ROM — 976 BYTES
USER FLASH VECTORS — 16 BYTES
IRQ
MODULE
POWER
PTA
DDRA
DDRE
PTE
INTERNAL BUS
OSC1
OSC2
(1), (2)
RST
(1), (3)
IRQ
V
DD
V
SS
PTA7/KBA7
(3)
PTE4/D–
(3) (4) (5)
PTE3/D+
(3) (4) (5)
PTE2/TCH1
(3)
PTE1/TCH0
(3)
PTE0/TCLK
(3)
PTB
DDRB
PTB7–PTB0
(3)
PTD
DDRD
PTD5–PTD2
(4) (5)
USB
MODULE
USB ENDPOINT 0, 1, 2
INTERNAL VOLTAGE REGULATOR
V
REG
(3.3 V)
(1) Pins have 5V logic.
(2) Pins have integrated pullup device.
(3) Pins have software configurable pullup device.
(4) Pins are open-drain when configured as output.
(5) Pins have 10mA sink capability.
(6) Pins have 25mA sink capability.
LS USB
TRANSCEIVER
BREAK
MODULE
OSCILLATOR
PTC
DDRC
PTC7–PTC0
(3)
KEYBOARD INTERRUPT
MODULE
POWER-ON RESET
MODULE
PTD7–PTD6
(4)
PTD1–PTD0
(4) (6)
PTA0/KBA0
(3)
: