Performance Motion Devices PR8358120, User Manual

Page: 38 / 103

Operation
38
Prodigy/CME PC/104 User’s Guide
2
is used with an address of 1. An amplifier enable signal will be changed only if the corresponding change mask bit is
set. The change mask bits are bits 8 – 11, the values to be loaded are bits 0 – 3.
Examples
In addition to the low-level
ReadIO
and
WriteIO
commands, the following commands are also supported in C-
Motion and VB-Motion: SetAmplifierEnable and GetAmplifierEnable . These commands provide a clearer and
simpler interface by handling the bit shifting.
2.3.2.1 Connections & associated signals
AmpEnable1-4 are direct digital outputs. There are no associated connections required for these signals to function
properly, however, one or more of the digital grounds must be connected. The power-up default value for all amplifier
enable signals is low (disabled). See Chapter
4, Electrical Reference , on page 69 for a complete description of the pinout
connections to and from the card.
2.3.3 DAC Output Enable
In addition to the amplifier enable outputs, there is a dedicated card function which allows the DAC output signals to
be shunted to 0 volts for safety purposes (DAC disabled), or to be controlled by the Magellan Motion Processor (DAC
enabled). This shunting occurs at a hardware level outside the motion processor itself, and provides an additional
safety layer to control the motor command.
The status of the DAC output enable function can be read using the ReadIO command, and the DAC output enable
status can be set using the WriteIO command, with an address of 1. The table in Section 2.3.2, “Amplifier Enable,”
on page 37 shows this. To read the status of the DAC output enable function, ReadIO is used. The value currently in
use will appear in bit 7. A value of 1 indicates DAC output is enabled, meaning that the voltage being output by the
DACs is controlled by the motion processor. A value of 0 indicates that it is disabled, meaning that the voltage being
output by the DAC is forced to 0.0 volts.
To enable or disable the DAC enable function, the WriteIO command is used. The change mask bit located at bit 15
must be loaded with a 1. Bit 8 must be loaded with a value of 0 to disable, or a value of 1 to enable output.
The powerup default value for DAC Output Enable is disabled. In addition, the DAC Output Enable is disabled upon
a card reset, or via the external
Reset
signal. See Section 2.6.2, “Reset,” on page 50 for more information.
Examples
In addition to the low-level ReadIO and WriteIO commands, the following commands are also supported in C-
Motion and VB-Motion: SetDACOutputEnable and GetDACOutputEnable . These commands provide a clearer
and simpler interface by handling the bit shifting.
WriteIO Address1, 0x0505 // write 0x0505 to I/O Address 1 to enable Amplifiers 1 & 3, don’t change 2 & 4
WriteIO Address1, 0x0400 // write 0x0400 to I/O Address 1 to disable Amplifier 3, don’t change 1, 2, & 4
WriteIO Address1, 0x0100 // write 0x0100 to I/O Address 1 to disable Amplifier 1, don’t change 2, 3, & 4
WriteIO Address1, 0x8080 // write 0x8080 to I/O Address 1 to enable all DACs,
// don’t change amplifier enables
WriteIO Address1, 0x8000 // write 0x8000 to I/O Address 1 to disable all DACs,
// don’t change amplifier enables