HCTL-1101 Datasheet, PDF (20/40 Pages) AVAGO TECHNOLOGIES LIMITED – General Purpose Control ICs Position and Velocity Control Low Power CMOS

Value written to R05H Action
00H
Software Reset
01H
Enter Init/Idle Mode
02H
Enter Align Mode (only from INIT/IDLE
Mode)
03H
Enter Control Mode (only from INIT/
IDLE Mode)
These Commands are discussed more detail in the “Oper-
ating Mode” section.
Status Register (R07H)
The Status register indicates the status of the HCTL-1101.
Each bit decodes into one signal. All 8 bits are user read-
able and are decoded as shown below. Only the lower 4
bits can be written to by the user to configure the HCTL-
1101. To set or clear any of the lower 4 bits, the user writes
an 8-bit word to R07H. The upper 4 bits are ignored. Each
of the lower 4 bits directly sets/clears the corresponding
bit of the Status register as shown below. For example,
writing XXXX0101 to R07H sets the PWM Sign Reversal
Inhibit, sets the Commutator Phase Configuration to “3
Phase,” and sets the Commutator Count Configuration to
“full.”
Table 3. Status Register
Status
Bit
0
1
Function
PWM Sign Reversal Inhibit :
0 = off 1 = on
Commutator Phase Configuration :
0 = 3 phase 1 = 4 phase
2
Commutator Count Configuration:
0 = quadrature 1 = full
3
Should always be set to 0
4
Trapezoidal Profile Flag F0:
1 = in Profile Control
5
Initialization/Idle Flag F1 :
1 = in Initialization/Idle Mode
6
STOP Flag :
0 = set (STOP triggered)
1 = cleared (no STOP)
7
LIMIT Flag :
0 = set (LIMIT triggered)
1 = cleared (no LIMIT)
Motor Command Register (R08H)
The 8-bit Motor Command Port consists of register R08H.
The register is connected to external pins MC0-MC7. MC7
is the most significant bit. R08H can be read and written
to; however, it should be written to only in the Initializa-
tion/Idle mode. During any of the four control modes, the
HCTL-1101 writes values to register R08H.
The Motor Command Port operates in two modes, bipolar
and unipolar, when under control of internal software. Bi-
polar mode allows the full range of values in R08H (-128D
to +127D). The data written to the Motor Command Port
by the control algorithms is the internally computed 2’s-
complement motor command with an 80H offset added.
This allows direct interfacing to a DAC. Connecting the
Motor Command Port to a DAC, Bipolar mode allows the
full voltage swing (positive and negative).
Unipolar mode functions such that with the same DAC
circuit, the motor command output is restricted to posi-
tive values (80H to FFH) when in a control mode. Unipolar
mode is used with multi-phase motors when the commu-
tator controls the direction of movement. (If needed, the
Sign pin could be used to indicate direction). In Unipolar
mode, the user can still write a negative value to R08H in
INIT/IDLE mode.
Unipolar mode or Bipolar mode is programmed by setting
or clearing flag F2 in the Flag Register R00H.
Internally, the HCTL-1101 operates on data of 24, 16 and
8 bit lengths to produce the 8-bit motor command, avail-
able externally. Many times the computed motor com-
mand will be greater than 8 bits. At this point, the motor
command is saturated by the controller. The saturated
value output by the controller is not the full scale value
00H (00D), or FFH (255D). The saturated value is adjusted
to 0FH (15D) (negative saturation) and F0H (240D) (posi-
tive saturation). Saturation levels for the Motor Command
port are in Figure 4.
PWM Motor Command Register (R09H)
The PWM port outputs the motor command as a pulse
width modulated signal with the correct sign of polar-
ity. The PWM port consists of the Pulse and Sign pins and
R09H.
The PWM signal at the Pulse pin has a frequency of Exter-
nal Clock/100 and the duty cycle is resolved into the 100
clocks. (For example, a 2 MHz clock gives a 20 KHz PWM
frequency.) The Sign pin gives the polarity of the com-
mand. Low output on Sign pin is positive polarity.
The 2’s-complement contents of R09H determine the duty
cycle and polarity of the PWM command. For example,
D8H (–40D) gives a 40% duty cycle signal at the Pulse pin
and forces the Sign pin high. Data outside the 64H (+100D)
to 9CH (–100D) linear range gives 100% duty cycle. R09H
can be read and written to. However, the user should only
write to R09H when the controller is in the Initialization/
Idle mode. Figure 5 shows the PWM output versus the in-
ternal motor command.
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