S9S08SG8E2MTJ Freescale Semiconductor, S9S08SG8E2MTJ Datasheet - Page 252

• Manufacturer Part Number: S9S08SG8E2MTJ
• Description: MCU 2K FLASH 20-TSSOP
• Manufacturer: Freescale Semiconductor
• Series: HCS08r

Specifications of S9S08SG8E2MTJ

• Core Processor: HCS08
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, LIN, SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Size: 8KB (8K 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 12x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 20-TSSOP
• Processor Series: S08SG
• Core: HCS08
• Data Bus Width: 8 bit
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWS08
• Development Tools By Supplier: DEMO9S08SG32, DEMO9S08SG32AUTO, DEMO9S08SG8, DEMO9S08SG8AUTO
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

Chapter 16 Timer/PWM Module (S08TPMV3)
to avoid such settings.) The TPM channel could still be used in output compare mode for software timing
functions (pin controls set not to affect the TPM channel pin).
16.4.1.2
An interrupt flag and enable are associated with the 16-bit main counter. The flag (TOF) is a
software-accessible indication that the timer counter has overflowed. The enable signal selects between
software polling (TOIE=0) where no hardware interrupt is generated, or interrupt-driven operation
(TOIE=1) where a static hardware interrupt is generated whenever the TOF flag is equal to one.
The conditions causing TOF to become set depend on whether the TPM is configured for center-aligned
PWM (CPWMS=1). In the simplest mode, there is no modulus limit and the TPM is not in CPWMS=1
mode. In this case, the 16-bit timer counter counts from 0x0000 through 0xFFFF and overflows to 0x0000
on the next counting clock. TOF becomes set at the transition from 0xFFFF to 0x0000. When a modulus
limit is set, TOF becomes set at the transition from the value set in the modulus register to 0x0000. When
the TPM is in center-aligned PWM mode (CPWMS=1), the TOF flag gets set as the counter changes
direction at the end of the count value set in the modulus register (that is, at the transition from the value
set in the modulus register to the next lower count value). This corresponds to the end of a PWM period
(the 0x0000 count value corresponds to the center of a period).
16.4.1.3
The main timer counter has two counting modes. When center-aligned PWM is selected (CPWMS=1), the
counter operates in up/down counting mode. Otherwise, the counter operates as a simple up counter. As
an up counter, the timer counter counts from 0x0000 through its terminal count and then continues with
0x0000. The terminal count is 0xFFFF or a modulus value in TPMxMODH:TPMxMODL.
When center-aligned PWM operation is specified, the counter counts up from 0x0000 through its terminal
count and then down to 0x0000 where it changes back to up counting. Both 0x0000 and the terminal count
value are normal length counts (one timer clock period long). In this mode, the timer overflow flag (TOF)
becomes set at the end of the terminal-count period (as the count changes to the next lower count value).
16.4.1.4
The main timer counter can be manually reset at any time by writing any value to either half of
TPMxCNTH or TPMxCNTL. Resetting the counter in this manner also resets the coherency mechanism
in case only half of the counter was read before resetting the count.
16.4.2
Provided CPWMS=0, the MSnB and MSnA control bits in the channel n status and control registers
determine the basic mode of operation for the corresponding channel. Choices include input capture,
output compare, and edge-aligned PWM.
252
Channel Mode Selection
Counter Overflow and Modulo Reset
Counting Modes
Manual Counter Reset
MC9S08SG8 MCU Series Data Sheet, Rev. 6
Freescale Semiconductor