Performance Motion Devices PR8358120, User Manual

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Operation
Prodigy/CME PC/104 User’s Guide
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To change the default values used by the card the PRP action Set sent to the Device resource is used. To read back the
current default parameters stored in the card the action Get is used. For detailed information on the format of these
PRP messages consult the Prodigy/CME Programmer’s Reference .
2.6.4 Dual-Ported RAM (Trace Buffer)
The Prodigy/CME PC/104 cards have 64 KBytes of on-card dual-ported memory (DPRAM) which is interfaced to
the Magellan Motion Processor as well as directly to the Prodigy/CME PC/104 card’s communications bus. Typically,
the dual-ported RAM is used to capture trace data from the Magellan Motion Processor. In this mode, its dual-port
configuration allows for high bandwidth access via the communications bus using PRP actions without affecting
Magellan command traffic. For more information on using the Magellan’s trace capability, see the
Magellan Motion
Processor User’s Guide .
The Magellan Motion Processor can be programmed to store information into the trace buffer using virtual buffers
of various sizes. Thus to correctly read the contents of the dual-ported RAM when used in this mode, you must know
the memory organization of the Magellan's trace function. See the
Magellan Motion Processor User’s Guide for details.
Another potential use of this RAM buffer is as a general purpose memory or register-based communications portal.
Since the dual-ported RAM is a resource addressable through the PRP system, the originator of the data, as well as the
retriever of the data, can be any device on, or external to, the card. While there are several possible ways to utilize the
dual-ported RAM in this way, the most common configuration is for the user application code of the C-Motion Engine
to collect and store data to the dual-ported RAM buffer, and to have an external host controller read it.
To read or write to the dual-ported RAM using the PRP system, a resource address must first be obtained by sending
the
Open action to the Memory resource. This resource address is used for all further access to the RAM. To write
data to the dual-ported RAM, the action Write is sent to the memory resource. To read the contents of the dual-ported
RAM, the action Read is used. Note that byte-sized memory operations are not supported to the dual-ported RAM.
For complete information on the format and function of these, and other PRP actions, refer to the Prodigy/CME
Programmer’s Reference .
2.6.5 Non-volatile Memory
The Prodigy/CME PC/104 cards have a general purpose 4,094 byte memory that retains its contents after a card
power down or reset. This memory is useful for storing parameters that are set only occasionally, and stay with the
card, such as machine calibration information.
Accessing the non-volatile memory is accomplished in the same manner as accessing the dual-ported RAM, except
that the NVRAM memory type is specified, instead of the DPRAM memory type. Addresses are specified from 0 to
4,093. When writing to this memory, a typical write takes 30

Secs, however under certain circumstances it can take
RS485 duplex Full
CANbus Communications
Baud Rate
1,000,000
Send Address 0x580
Receive Address 0x600
Task Control & User Application Code
Auto start (y/n)
Yes
Console channel Serial 2
The contents of the dual-ported RAM are volatile. They are not saved during power-down of the card.
Parameter Factory default value