MC908JB16DWE Datasheet, PDF (123/332 Pages) Freescale Semiconductor, Inc – Microcontrollers

Technical Data — MC68HC908JB16
Section 9. Monitor ROM (MON)
9.1 Contents
9.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
9.3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
9.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124
9.4.1 Entering Monitor Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
9.4.2 Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
9.4.3 Break Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
9.4.4 Baud Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .129
9.4.5 Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
9.5 Security. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
9.5.1 Extended Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
9.2 Introduction
This section describes the monitor ROM (MON) and the monitor mode
entry methods. The monitor ROM allows complete testing of the MCU
through a single-wire interface with host computer. This mode is also
used for programming and erasing of FLASH memory in the MCU.
Monitor mode entry can be achieved without use of the higher voltage,
V_TST, as long as vector addresses $FFFE and $FFFF are blank, thus
reducing the hardware requirements for in-circuit programming.
MC68HC908JB16 — Rev. 1.1
Freescale Semiconductor
Monitor ROM (MON)
Technical Data
123