MC9S08GT32CFDE Freescale Semiconductor, MC9S08GT32CFDE Datasheet - Page 247

• Manufacturer Part Number: MC9S08GT32CFDE
• Description: IC MCU 32K FLASH 20MHZ 48-QFN
• Manufacturer: Freescale Semiconductor
• Series: HCS08r

Specifications of MC9S08GT32CFDE

• Core Processor: HCS08
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 39
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 3.6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-QFN
• Controller Family/series: HCS08
• No. Of I/o's: 39
• Ram Memory Size: 2KB
• Cpu Speed: 40MHz
• No. Of Timers: 2
• Rohs Compliant: Yes
• For Use With: M68DEMO908GB60E - BOARD DEMO MC9S08GB60M68EVB908GB60E - BOARD EVAL FOR MC9S08GB60
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

On-Chip Debug System (DBG)
A force-type breakpoint waits for the current instruction to finish and then acts upon the breakpoint
request. The usual action in response to a breakpoint is to go to active background mode rather than
continuing to the next instruction in the user application program.
The tag vs. force terminology is used in two contexts within the debug module. The first context refers to
breakpoint requests from the debug module to the CPU. The second refers to match signals from the
comparators to the debugger control logic. When a tag-type break request is sent to the CPU, a signal is
entered into the instruction queue along with the opcode so that if/when this opcode ever executes, the CPU
will effectively replace the tagged opcode with a BGND opcode so the CPU goes to active background
mode rather than executing the tagged instruction. When the TRGSEL control bit in the DBGT register is
set to select tag-type operation, the output from comparator A or B is qualified by a block of logic in the
debug module that tracks opcodes and only produces a trigger to the debugger if the opcode at the compare
address is actually executed. There is separate opcode tracking logic for each comparator so more than one
compare event can be tracked through the instruction queue at a time.
15.4.5
Trigger Modes
The trigger mode controls the overall behavior of a debug run. The 4-bit TRG field in the DBGT register
selects one of nine trigger modes. When TRGSEL = 1 in the DBGT register, the output of the comparator
must propagate through an opcode tracking circuit before triggering FIFO actions. The BEGIN bit in
DBGT chooses whether the FIFO begins storing data when the qualified trigger is detected (begin trace),
or the FIFO stores data in a circular fashion from the time it is armed until the qualified trigger is detected
(end trigger).
A debug run is started by writing a 1 to the ARM bit in the DBGC register, which sets the ARMF flag and
clears the AF and BF flags and the CNT bits in DBGS. A begin-trace debug run ends when the FIFO gets
full. An end-trace run ends when the selected trigger event occurs. Any debug run can be stopped manually
by writing a 0 to the ARM bit or DBGEN bit in DBGC.
In all trigger modes except event-only modes, the FIFO stores change-of-flow addresses. In event-only
trigger modes, the FIFO stores data in the low-order eight bits of the FIFO.
The BEGIN control bit is ignored in event-only trigger modes and all such debug runs are begin type
traces. When TRGSEL = 1 to select opcode fetch triggers, it is not necessary to use R/W in comparisons
because opcode tags would only apply to opcode fetches that are always read cycles. It would also be
unusual to specify TRGSEL = 1 while using a full mode trigger because the opcode value is normally
known at a particular address.
The following trigger mode descriptions only state the primary comparator conditions that lead to a trigger.
Either comparator can usually be further qualified with R/W by setting RWAEN (RWBEN) and the
corresponding RWA (RWB) value to be matched against R/W. The signal from the comparator with
optional R/W qualification is used to request a CPU breakpoint if BRKEN = 1 and TAG determines
whether the CPU request will be a tag request or a force request.
MC9S08GB/GT Data Sheet, Rev. 2.3
Freescale Semiconductor
247