Echelon Product Alerts
Problem: Intermittent data loss when using the SPI Clock Setting of 0 with the FT 5000 Smart Transceiver or Neuron 5000 Processor at 80 MHz Solution: Use a slower SPI Clock Setting or a slower system clock rate |
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Date
December 13, 2010
Products Affected
FT 5000 Smart Transceiver (Model No: 14235R) and Neuron® 5000 Processor (Model No: 14305R)
Summary
An FT 5000 Smart Transceiver or a Neuron 5000 Processor running Neuron firmware version 19 with an 80 MHz system clock setting can experience intermittent data loss when using the Synchronous Peripheral Interface (SPI) I/O model in a Neuron C program at the fastest SPI clock setting (20MHz SPI clock).
For an FT 5000 Smart Transceiver or a Neuron 5000 Processor running with an 80 MHz system clock, specifying the fastest SPI clock setting (using the Neuron C clock(0)keyword in the SPI I/O model declaration) can cause intermittent data loss. The problem does not occur for other SPI clock rate settings or for other system clock rates. The problem occurs only for an FT 5000 Smart Transceiver or a Neuron 5000 Processor running as an SPI slave device. The problem applies only to received data; transmitted data is not affected.
The problem arises for data that is received by the SPI master on the MISO signal while it is clocking data to and from the SPI slave. For the combination of an 80 MHz system clock with SPI clock clock(0), the MISO data setup time at the master can be violated , which can cause data corruption.
For more information about the SPI I/O model, see the I/O Model Reference for Smart Transceivers and Neuron Chips (078-0392-01B).
Solution
Do not specify clock(0)in your Neuron C program for an FT 5000 Smart Transceiver or a Neuron 5000 Processor running with an 80 MHz system clock.
For an 80 MHz system clock, you can specify any of the other SPI clock rates: clock(1), clock(2), clock(3), clock(4), clock(5), clock(6), or clock(7).
For a lower system clock setting (40 MHz, 20 MHz, 10 MHz, or 5 MHz), you can specify any of the SPI clock rates.
If you require further assistance, please contact the nearest Echelon support office.