hostmot2.9

CNC 的开放码,EMC2 V2.2.8版

the pwmgen instances running in the PWM modes (modes 1 and 2).  This is
the frequency of the variable-duty-cycle wave.  Its effective range is
from 1 Hz up to 193 KHz.  Note that the max frequency is determined by the
ClockHigh frequency of the Anything IO board; the 5i20 and 7i43 both have
a 100 MHz clock, resulting in a 193 KHz max PWM frequency.  Other boards
may have different clocks, resulting in different max PWM frequencies.
If the user attempts to set the frequency too high, it will be clipped
to the max supported frequency of the board.  Frequencies below about
5 Hz are not terribly accurate, but above 5 Hz they're pretty close.

(u32 rw) pdm_frequency: This specifies the PDM frequency, in Hz, of
all the pwmgen instances running in PDM mode (mode 3).  This is the
"pulse slot frequency"; the frequency at which the pdm generator in the
AnyIO board chooses whether to emit a pulse or a space.  Each pulse (and
space) in the PDM pulse train has a duration of 1/pdm_frequency seconds.
For example, setting the pdm_frequency to 2e6 (2 MHz) and the duty cycle
to 50% results in a 1 MHz square wave, identical to a 1 MHz PWM signal
with 50% duty cycle.  The effective range of this parameter is from
about 1525 Hz up to just under 100 MHz.  Note that the max frequency
is determined by the ClockHigh frequency of the Anything IO board; the
5i20 and 7i43 both have a 100 MHz clock, resulting in a 100 Mhz max PDM
frequency.  Other boards may have different clocks, resulting in different
max PDM frequencies.  If the user attempts to set the frequency too high,
it will be clipped to the max supported frequency of the board.
.SH stepgen

stepgens have names like "hm2_<BoardType>.<BoardNum>.stepgen.<Instance>".
"Instance" is a two-digit number that corresponds to the HostMot2 stepgen
instance number.  There are 'num_stepgens' instances, starting with 00.

Each stepgen allocates 2-6 IO pins (selected at firmware compile time),
but currently only uses two: Step and Direction outputs.

The stepgen representation is modeled on the stepgen software component.
Each stepgen instance has the following pins and parameters:

Pins:

(float input) position-cmd: Target of stepper motion, in arbitrary
position units.

(s32 output) counts: Feedback position in counts (number of steps).

(float output) position-fb: Feedback position in arbitrary position units
(counts / position_scale).

(float output) velocity-fb: Feedback velocity in arbitrary position
units per second.

(bit input) enable: Enables output steps.  When false, no steps are
generated.

Parameters:

(float r/w) position-scale: Converts from counts to position units.
position = counts / position_scale

(float r/w) maxvel: Maximum speed, in position units per second.  If set
to 0, the driver will choose the maximum velocity based on the values of
steplen and stepspace (at the time that maxvel was set to 0).

(float r/w) maxaccel: Maximum acceleration, in position units per second
per second.  If set to 0, the driver will not limit its acceleration.

(u32 r/w) steplen: Duration of the step signal, in nanoseconds.

(u32 r/w) stepspace: Minimum interval between step signals, in
nanoseconds.

(u32 r/w) dirsetup: Minimum duration of stable Direction signal before
a step begins, in nanoseconds.

(u32 r/w) dirhold: Minimum duration of stable Direction signal after a
step ends, in nanoseconds.

(u32 r/w) step_type: Output format, like the step_type modparam to the
software stegen(9) component.  0 = Step/Dir, 1 = Up/Down, 2 = Quadrature.
In Quadrature mode (step_type=2), the stepgen outputs one complete Gray
cycle (00 -> 01 -> 11 -> 10 -> 00) for each "step" it takes.
.SH General Purpose I/O

I/O pins on the board which are not used by a module instance are exported
to HAL as full GPIO pins.  Full GPIO pins can be configured at run-time
to be inputs, outputs, or open drains, and have a HAL interface that
exposes this flexibility.  IO pins that are owned by an active module
instance are constrained by the requirements of the owning module,
and have a restricted HAL interface.

GPIOs have names like
"hm2_<BoardType>.<BoardNum>.gpio.<PortName>.<PinNum>".  PinNum is a
three-digit number.  PortName and PinNum correspond to the I/O Pin info
as given in Mesa Electronics' manual for the board.

Each GPIO can have the following HAL Pins:

(bit out) in & in_not: State (normal and inverted) of the hardware
input pin.  This follows the Canonical Device Interface for Digital Input.
Only full GPIO pins and IO pins used as inputs by active module instances
have these pins.

(bit in) out: Value to be written (possibly inverted) to the hardware
output pin.  This follows the Canonical Device Interface for Digital
Output.  Only full GPIO pins have this pin.

Each GPIO can have the following Parameters:

(bit r/w) is_output: If set to 0, the GPIO is an input.  The IO pin is
put in a high-impedance state (pulled up to 5V), to be driven by other
devices.  The logic value on the IO pin is available in the "in" and
"in_not" HAL pins.  Writes to the "out" HAL pin have no effect.  If this
parameter is set to 1, the GPIO is an output; its behavior then depends
on the "is_opendrain" parameter.  Only full GPIO pins have this parameter.

(bit r/w) is_opendrain: This parameter only has an effect if the
"is_output" parameter is true.  If this parameter is false, the GPIO
behaves as a normal output pin: the IO pin on the connector is driven
to the value specified by the "out" HAL pin (possibly inverted), and the
value of the "in" and "in_not" HAL pins is undefined.  If this parameter
is true, the GPIO behaves as an open-drain pin.  Writing 0 to the "out"
HAL pin drives the IO pin low, writing 1 to the "out" HAL pin puts the
IO pin in a high-impedance state.  In this high-impedance state the IO
pin floats (pulled up to 5V), and other devices can drive the value; the
resulting value on the IO pin is available on the "in" and "in_not" pins.
Only full GPIO pins and IO pins used as outputs by active module instances
have this parameter.

(bit r/w) invert_output: This parameter only has an effect if the
"is_output" parameter is true.  If this parameter is true, the output
value of the GPIO will be the inverse of the value on the "out" HAL pin.
This corresponds to the 'invert' parameter in the Canonical Device
Interface for Digital Output.  Only full GPIO pins and IO pins used as
outputs by active module instances have this parameter.
.SH Watchdog

The HostMot2 firmware may include a watchdog Module; if it does, the
hostmot2 driver will use it.

The watchdog must be petted by EMC2 periodically or it will bite.

When the watchdog bites, all the board's I/O pins are disconnected from
their Module instances and become high-impedance inputs (pulled high),
and all communication with the board stops.  The state of the HostMot2
firwmare modules is not disturbed (except for the configuration of the
IO Pins).  Encoder instances keep counting quadrature pulses, and pwm-
and step-generators keep generating signals (which are *not* relayed to
the motors, because the IO Pins have become inputs).

Resetting the watchdog resumes communication and resets the I/O pins to
the configuration chosen at load-time.

If the firmware includes a watchdog, the following HAL objects will
be exported:

Pins:

(bit in/out) has_bit: True if the watchdog has bit, False if the watchdog has
not bit.  If the watchdog has bit and the has_bit bit is True, the user
can reset it to False to resume operation.

Parameters:

(u32 read/write) timeout_ns: Watchdog timeout, in nanoseconds.  This is initialized
to 1,000,000,000 (1 second) at module load time.  If more than this
amount of time passes between calls to the pet_watchdog() function,
the watchdog will bite.

Functions:

pet_watchdog(): Calling this function resets the watchdog timer and
postpones the watchdog biting until timeout_ns nanoseconds later.
.SH Raw Mode

If the "enable_raw" config keyword is specified, some extra debugging
options are made available to HAL.  With Raw mode enabled, a user may
peek and poke the firmware from HAL, and may dump the internal state of
the hostmot2 driver to the syslog.

Pins:

(u32 in) read_address: The bottom 16 bits of this is used as the address
to read from.

(u32 out) read_data: Each time the hm2_read() function is called, this
pin is updated with the value at .read_address.

(u32 in) write_address: The bottom 16 bits of this is used as the address
to write to.

(u32 in) write_data: This is the value to write to .write_address.

(bit in) write_strobe: Each time the hm2_write() function is called, this
pin is examined.  If it is True, then value in .write_data is written
to the address in .write_address, and .write_strobe is set back to False.

(bit in/out) dump_state: This pin is normally False.  If it gets set to
True the hostmot2 driver will write its representation of the board's
internal state to the syslog, and set the pin back to False.
.SH FUNCTIONS
.TP
\fBhm2_<BoardType>.<BoardNum>.read\fR
Read all inputs, update input HAL pins.
.TP
\fBhm2_<BoardType>.<BoardNum>.write\fR
Write all outputs.
.TP
\fBhm2_<BoardType>.<BoardNum>.pet-watchdog\fR
Pet the watchdog to keep it from biting us for a while.
.TP
\fBhm2_<BoardType>.<BoardNum>.read_gpio\fR
Read the GPIO input pins. (This function is not available on the 7i43
due to limitations of the EPP bus.)
.TP
\fBhm2_<BoardType>.<BoardNum>.write_gpio\fR
Write the GPIO control registers and output pins.  (This function is
not available on the 7i43 due to limitations of the EPP bus.)
.SH SEE ALSO

hm2_7i43(9)
.br
hm2_pci(9)
.br
Mesa's documentation for the Anything I/O boards, at <http://www.mesanet.com>
.br
.SH LICENSE

GPL