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SM-Universal Encoder Plus User Guide
59
Issue Number: 6 www.controltechniques.com
Data should be written to the transmit buffer when the buffer has been reset to zero by
the module. The data will be transferred to the comms buffer and the transmit register
will be cleared. Data can be read from the receive buffer at any time. If there is receive
data in the buffer bit 15 will be set. Once the data has been read the buffer should be
cleared and the module will then transfer more data. The buffer is 16 bytes long and any
messages that exceed this length (including the checksum added for Hiperface) will
cause an error. The status flags are defined as follows:
SC.HiPEr
The Stegmann Hiperface comms protocol is an asynchronous byte based system. Up to
15 bytes of data can be written to the buffer. The first byte should be the encoder
address. The checksum will be calculated by the module and added to the end of the
message before the message is transmitted to the encoder. The module checks the
checksum of the received message. If successfully received, the receive message can
be read via the receive register including the address and the checksum received from
the encoder. It should be noted that the encoder must be set up for 9600 baud, 1 start
bit, 1 stop bit and even parity (default set-up) for the encoder comms to operate with the
module. Also the data block security should not be enabled if the SM-Encoder
nameplate system is to operate correctly.
Register Bit Function
Transmit 15
Must be set for the Solutions Module to transfer the LS byte to the
comms buffer.
Transmit 14
The LS byte is the last byte of the message and this byte should be
put in the comms buffer and be transferred to the encoder.
Transmit 13
The LS byte is the first byte of the message. (If this is used the buffer
pointer is reset to the start of the buffer.)
Receive 15
Indicates data from the last transfer can be read from the receive
buffer.
Receive 14 The byte in the LS byte is the last byte of the receive message
Receive 13
There is no data in the receive buffer and the LS byte is the comms
system status. If there was an error in the received message this will
always be set and one of the status error bits will be set until the
comms is used again by this system.
Bit Meaning
0
The number of bytes put into the transmit buffer is not consistent with the expected
message length.
1
The number of bytes written to the transmit buffer, or the expected length of the store
data transmit message, or the expected length of a read data message have exceed
the length of the buffer.
2 The command code is not supported.
3 The encoder has signalled an error.
4 There was an error in the checksum/CRC of the received message.
5 A timeout occurred.
6
The last message was to auto-configure the drive encoder and the encoder was
identified successfully.
7
The last message was initiated through the Solutions Module interface or from the drive
electronic nameplate system and the last message was successful.