Chapter 10 Stepper Stall Detector (SSDV1)
MC9S12HZ256 Data Sheet, Rev. 2.04
298
Freescale Semiconductor
10.3.2.3
Stepper Stall Detector Control Register (SSDCTL)
Read: anytime
Write: anytime
l
3
FLMC
Force Load Register into the Modulus Counter Count Register — This bit always reads zero.
0 Write zero to this bit has no effect.
1 Write one into this bit loads the load register into the modulus counter count register.
2
MCEN
Modulus Down-Counter Enable
0 Modulus down-counter is disabled. The modulus counter (MDCCNT) is preset to 0xFFFF. This will prevent an
early interrupt ag when the modulus down-counter is enabled.
1 Modulus down-counter is enabled.
0
AOVIE
Accumulator Overow Interrupt Enable
0 Interrupt disabled.
1 Interrupt enabled. An interrupt will be generated when the accumulator overow interrupt ag (AOVIF) is set.
76543210
R
RTZE
SDCPU
SSDWAI
FTST
00
ACLKS
W
Reset
0
00000
= Unimplemented or Reserved
Figure 10-4. Stepper Stall Detector Control Register (SSDCTL)
Table 10-8. SSDCTL Field Descriptions
Field
Description
7
RTZE
Return to Zero Enable — If this bit is set, the coils are controlled by the SSD and are congured into one of the
four full step states as shown in
Table 10-6. If this bit is cleared, the coils are not controlled by the SSD.
0 RTZ is disabled.
1 RTZ is enabled.
6
SDCPU
Sigma-Delta Converter Power Up — This bit provides on/off control for the sigma-delta converter allowing
reduced MCU power consumption. Because the analog circuit is turned off when powered down, the sigma-delta
converter requires a recovery time after it is powered up.
0 Sigma-delta converter is powered down.
1 Sigma-delta converter is powered up.
5
SSDWAI
SSD Disabled during Wait Mode — When entering Wait Mode, this bit provides on/off control over the SSD
allowing reduced MCU power consumption. Because the analog circuit is turned off when powered down, the
sigma-delta converter requires a recovery time after exit from Wait Mode.
0 SSD continues to run in WAIT mode.
1 Entering WAIT mode freezes the clock to the prescaler divider, powers down the sigma-delta converter, and
if RTZE bit is set, the sine and cosine coils are recirculated via VSSM.
Table 10-7. MDCCTL Field Descriptions (continued)
Field
Description