Overview
The MC9S08GB/GT are members of the low-cost, high-performance HCS08 Family of 8-bit microcontroller units (MCUs). All MCUs in the family use the enhanced HCS08 core and are available with a variety of modules, memory sizes, memory types, and package types.

FEATUREs
Features have been organized to reflect:
• Standard features of the HCS08 Family
• Features of the MC9S08GB/GT MCU

Standard Features of the HCS08 Family
• 40-MHz HCS08 CPU (central processor unit)
• HC08 instruction set with added BGND instruction
• Background debugging system (see also the Development Support section)
• Breakpoint capability to allow single breakpoint setting during in-circuit debugging (plus two more breakpoints in on-chip debug module)
• Debug module containing two comparators and nine trigger modes. Eight deep FIFO for storing change-of-flow addresses and event-only data. Debug module supports both tag and force breakpoints.
• Support for up to 32 interrupt/reset sources
• Power-saving modes: wait plus three stops
• System protection features:
   – Optional computer operating properly (COP) reset
   – Low-voltage detection with reset or interrupt
   – Illegal opcode detection with reset
   – Illegal address detection with reset (some devices don’t have illegal addresses)

FEATUREs of MC9S08GB/GT Series of MCUs
• On-chip in-circuit programmable FLASH memory with block protection and security options (see Table 1-1 for device specific information)
• On-chip random-access memory (RAM) (see Table 1-1 for device specific information)
• 8-channel, 10-bit analog-to-digital converter (ATD)
• Two serial communications interface modules (SCI)
• Serial peripheral interface module (SPI)
• Clock source options include crystal, resonator, external clock or internally generated clock with precision NVM trimming
• Inter-integrated circuit bus module to operate up to 100 kbps (IIC)
• One 3-channel and one 5-channel 16-bit timer/pulse width modulator (TPM) modules with selectable input capture, output compare, and edge-aligned PWM capability on each channel. Each timer module may be configured for buffered, centered PWM (CPWM) on all channels (TPMx).
• 8-pin keyboard interrupt module (KBI)
• 16 high-current pins (limited by package dissipation)
• Software selectable pullups on ports when used as input. Selection is on an individual port bit basis. During output mode, pullups are disengaged.
• Internal pullup on RESET and IRQ pin to reduce customer system cost
• 56 general-purpose input/output (I/O) pins, depending on package selection
• 64-pin low-profile quad flat package (LQFP) — MC9S08GBxx
• 44-pin quad flat package (QFP) — MC9S08GTxx
• 42-pin shrink dual in-line package (SDIP) — MC9S08GTxx