MC9S12HZ256 Datasheet, PDF (306/692 Pages) Freescale Semiconductor, Inc – HCS12 Microcontrollers

Chapter 10 Stepper Stall Detector (SSDV1)
10.4.3 Operation in Low Power Modes
The SSD block can be configured for lower MCU power consumption in three different ways.
• Stop mode powers down the sigma-delta converter and halts clock to the modulus counter. Exit
from Stop enables the sigma-delta converter and the clock to the modulus counter but due to the
converter recovery time, the integration result should be ignored.
• Wait mode with SSDWAI bit set powers down the sigma-delta converter and halts the clock to the
modulus counter. Exit from Wait enables the sigma-delta converter and clock to the modulus
counter but due to the converter recovery time, the integration result should be ignored.
• Clearing SDCPU bit powers down the sigma-delta converter.
10.4.4 Stall Detection Flow
Figure 10-15 shows a flowchart and software setup for stall detection of a stepper motor. To control a
second stepper motor, the SMS bit must be toggled during the SSD initialization.
MC9S12HZ256 Data Sheet, Rev. 2.04
306
Freescale Semiconductor