MC9S08GT16CFB Freescale Semiconductor, MC9S08GT16CFB Datasheet - Page 240

• Manufacturer Part Number: MC9S08GT16CFB
• Manufacturer: Freescale Semiconductor

Specifications of MC9S08GT16CFB

• Cpu Family: HCS08
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: SCI/SPI
• Program Memory Type: Flash
• Program Memory Size: 16KB
• Total Internal Ram Size: 1KB
• # I/os (max): 36
• Number Of Timers - General Purpose: 4
• Operating Supply Voltage (typ): 2.5/3.3V
• Operating Supply Voltage (max): 3.6V
• Operating Supply Voltage (min): 2.08V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 44
• Package Type: PQFP
• Lead Free Status / Rohs Status: Not Compliant

Development Support
Figure 15-3
shows the host receiving a logic 1 from the target HCS08 MCU. Because the host is
asynchronous to the target MCU, there is a 0-to-1 cycle delay from the host-generated falling edge on
BKGD to the perceived start of the bit time in the target MCU. The host holds the BKGD pin low long
enough for the target to recognize it (at least two target BDC cycles). The host must release the low drive
before the target MCU drives a brief active-high speedup pulse seven cycles after the perceived start of the
bit time. The host should sample the bit level about 10 cycles after it started the bit time.
BDC CLOCK
(TARGET MCU)
HOST DRIVE
HIGH-IMPEDANCE
TO BKGD PIN
TARGET MCU
SPEEDUP PULSE
HIGH-IMPEDANCE
HIGH-IMPEDANCE
PERCEIVED START
OF BIT TIME
R-C RISE
BKGD PIN
10 CYCLES
EARLIEST START
OF NEXT BIT
10 CYCLES
HOST SAMPLES BKGD PIN
Figure 15-3. BDC Target-to-Host Serial Bit Timing (Logic 1)
MC9S08GB/GT Data Sheet, Rev. 2.3
240
Freescale Semiconductor