MC908JB8ADWE Freescale Semiconductor, MC908JB8ADWE Datasheet - Page 175

• Manufacturer Part Number: MC908JB8ADWE
• Description: IC MCU 3MHZ 8K FLASH 28-SOIC
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC908JB8ADWE

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 3MHz
• Connectivity: USB
• Peripherals: LVD, POR, PWM
• Number Of I /o: 21
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-SOIC (7.5mm Width)
• Processor Series: HC08JB
• Core: HC08
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: USB
• Maximum Clock Frequency: 3 MHz
• Number Of Programmable I/os: 37
• Number Of Timers: 2
• Operating Supply Voltage: 5.25 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Development Tools By Supplier: FSICEBASE, DEMO908GZ60E, M68EML08GZE, KITUSBSPIDGLEVME, KITUSBSPIEVME, KIT33810EKEVME
• Minimum Operating Temperature: 0 C
• Controller Family/series: HC08
• No. Of I/o's: 21
• Ram Memory Size: 256Byte
• Cpu Speed: 8MHz
• No. Of Timers: 1
• Embedded Interface Type: SCI, SPI
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

10.5 Security
MC68HC908JB8•MC68HC08JB8•MC68HC08JT8 — Rev. 2.3
Freescale Semiconductor
NOTE:
A security feature discourages unauthorized reading of FLASH locations
while in monitor mode. The host can bypass the security feature at
monitor mode entry by sending eight security bytes that match the bytes
at locations $FFF6–$FFFD. Locations $FFF6–$FFFD contain user-
defined data.
Do not leave locations $FFF6–$FFFD blank. For security reasons,
program locations $FFF6–$FFFD even if they are not used for vectors.
During monitor mode entry, the MCU waits after the power-on reset for
the host to send the eight security bytes on pin PTA0. If the received
bytes match those at locations $FFF6–$FFFD, the host bypasses the
security feature and can read all FLASH locations and execute code
from FLASH. Security remains bypassed until a power-on reset occurs.
If the reset was not a power-on reset, security remains bypassed and
security code entry is not required. (See
PTA0
V
RST
NOTES:
DD
1 = Echo delay, 2 bit times
2 = Data return delay, 2 bit times
4 = Wait 1 bit time before sending next byte.
FROM HOST
FROM MCU
Figure 10-7. Monitor Mode Entry Timing
Monitor ROM (MON)
4096 + 32 OSCXCLK CYCLES
24 BUS CYCLES
1
4
1
Figure
10-7.)
1
Monitor ROM (MON)
2
Technical Data
4
1
Security
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