MC68HC908SR12CB Freescale Semiconductor, MC68HC908SR12CB Datasheet - Page 166

• Manufacturer Part Number: MC68HC908SR12CB
• Description: IC MCU 12K FLASH 8MHZ 42-SDIP
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC68HC908SR12CB

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: I²C, SCI
• Peripherals: LVD, POR, PWM, Temp Sensor
• Number Of I /o: 29
• Program Memory Size: 12KB (12K x 8)
• Program Memory Type: FLASH
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 11x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 42-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

Monitor ROM (MON)
10.3 Features
10.4 Functional Description
Data Sheet
166
Features of the monitor ROM include:
The monitor ROM receives and executes commands from a host
computer.
mode and communicate with a host computer via a standard RS-232
interface.
Simple monitor commands can access any memory address. In monitor
mode, the MCU can execute code downloaded into RAM by a host
computer while most MCU pins retain normal operating mode functions.
All communication between the host computer and the MCU is through
the PTA0 pin. A level-shifting and multiplexing interface is required
between PTA0 and the host computer. PTA0 is used in a wired-OR
configuration and requires a pullup resistor.
1. No security feature is absolutely secure. However, Freescale’s strategy is to make reading or
copying the FLASH difficult for unauthorized users.
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Normal user-mode pin functionality
One pin dedicated to serial communication between monitor ROM
and host computer
Standard mark/space non-return-to-zero (NRZ) communication
with host computer
Execution of code in RAM or FLASH
FLASH memory security feature
FLASH memory programming interface
Enhanced PLL (phase-locked loop) option to allow use of external
32.768-kHz crystal to generate internal frequency of 2.4576 MHz
368 bytes monitor ROM code size ($FE10 to $FF7F)
Monitor mode entry without high voltage, V
blank ($FFFE and $FFFF contain $FF)
Standard monitor mode entry if high voltage, V
IRQ1
Figure 10-1
Monitor ROM (MON)
shows an example circuit used to enter monitor
MC68HC908SR12•MC68HC08SR12 — Rev. 5.0
1
TST
Freescale Semiconductor
, if reset vector is
TST
, is applied to