SSI output configuration

Description

The behavior of the SSI interface can be configured via IO-Link. Normally the SSI supports only one output data but with this product additional data can be enabled that follows directly after the main data.

Some properties of the additional data can be configured independently, though with limited options.

Main data

This is the primary data for the SSI output. This data is transmitted first (the length is determined by the SSI configuration parameter Number of bits).

The following is available as main data:

Position of the first position magnet
Position difference

Additional data

If the SSI additional data enable parameter is set to true, the selected data is inserted after the main data.

The following is available as additional data:

Position of the second position magnet
Velocity of the first position magnet (signed)
Velocity of the first position magnet (absolute)
Position difference
Internal temperature
Movement distance
Total operating time

ISDU

SSI output configuration – ISDU
Name	Index	Subindex	Access	Length	Data Type	Data Storage	Default
SSI data selector	0x0124 (292)	0	R/W	2	ENUM (UINT16)	Yes	0x0000 (0)
SSI configuration	0x0125 (293)	0	R/W	16	RECORD	Yes
Coding		1	R/W	1	ENUM (UINT8)	No	0x00 (0)
Representation		2	R/W	1	ENUM (UINT8)	No	0x00 (0)
Parity mode		3	R/W	1	ENUM (UINT8)	No	0x00 (0)
Error bit enable		4	R/W	1	BOOL	No	0x00 (0)
Multiple transmission enable		5	R/W	1	BOOL	No	0x00 (0)
Adaptive timeout enable		6	R/W	1	BOOL	No	0x00 (0)
Invert		7	R/W	1	BOOL	No	0x00 (0)
Number of bits		8	R/W	1	UINT8	No	0x18 (24)
Timeout		9	R/W	2	UINT16	No
Hysteresis		10	R/W	2	UINT16	No
Error value		11	R/W	4	INT32	No	0x7FFFFFFF (2147483647)
SSI resolution	0x0126 (294)	0	R/W	2	ENUM (UINT16)	Yes	0x0002 (2)
SSI offset	0x0127 (295)	0	R/W	4	INT32	Yes	0x00000000 (0)
SSI additional data enable	0x0142 (322)	0	R/W	1	BOOL	Yes	0x00 (0)
SSI additional data selector	0x0143 (323)	0	R/W	2	ENUM (UINT16)	Yes	0x0001 (1)
SSI additional data configuration	0x0144 (324)	0	R/W	8	ENUM (UINT16)	Yes
Invert		1	R/W	1	BOOL	No	0x00 (0)
Number of bits		2	R/W	1	UINT8	No	0x18 (24)
Hysteresis		3	R/W	2	UINT16	No
Error value		4	R/W	4	INT32	No	0x7FFFFFFF (2147483647)
SSI additional data resolution	0x0145 (325)	0	R/W	2	ENUM (UINT16)	Yes	0x0002 (2)
SSI additional data offset	0x0146 (326)	0	R/W	4	INT32	Yes	0x00000000 (0)

SSI output data selector

SSI output data selector – options
Value	Meaning
0x00 (0)	Position of position magnet 1
0x04 (4)	Position difference

SSI configuration

Coding

This parameter is used to select between binary and Gray coding. It affects both the encoding of the main data and that of the supplementary data, however with Gray coding the two values are coded seperately.

SSI configuration – coding
Value	Meaning
0x00 (0)	Binary
0x01 (1)	Gray

Representation

Selects between two’s complement and sign and magnitude representations. This parameter affeccts both main and additional data’s representation.

SSI configuration – representation
Value	Meaning
0x00 (0)	Two’s complement
0x01 (1)	Sign and magnitude

Parity mode

Controls the parity bit mode for the main data only.

SSI configuration – parity mode
Value	Meaning
0x00 (0)	Parity disabled
0x01 (1)	Even parity
0x02 (2)	Odd parity

Note

Enabling the parity bit reduces the number of bits available for the main data.

For example if the Number of bits is set to 24 and the parity bit is enabled (even or odd), the remaining 23 bits are used to represent the actual value.

Note

When parity is enabled, it is always the MSB.

Error bit enable

If the parameter is set to true, an error bit is inserted before the main data.

Note

Enabling the error bit reduces the number of bits available for the main data.

For example if the Number of bits is set to 24 and the error bit is enabled, the remaining 23 bits are used to represent the actual value.

Multiple transmission enable

Set this parameter to true to enable multiple transmission. For more details see operation principle.

Adaptive timeout enable

If adaptive timeout is disabled, the monoflop timeout is set to Timeout. If adaptive timeout is enabled, the monoflop timeout is derived from the SSI clock frequency (twice the clock period).

For details, see operation principle.

Invert

This parameter inverts the output characteristic.

Note

Invert is only for position data.

Number of bits

This field specifies that how many bits are used to represent the main data. The Number of bits must be between 16 and 32 (inclusive) and can be configured in increments of 1 bit. If the additional data is enabled, the total number of bits must be less than or equal to 48.

Note

The Number of bits includes the error and / or parity bit if enabled.

For example: to have 24 bit position data with error and parity bit, the Number of bits parameter must be set to 26.

Timeout

Specifies the SSI monoflop timeout in microseconds (μs). This value must be between 1 and 500 μs (inclusive).

Hysteresis

Specifies the position hysteresis. The unit is micrometer (μm). The value must be between 0 and 10.000 (inclusive).

../../../_images/ssi_char_hyst.png — SSI output characteristic - hysteresis

Error value

This parameter defines the substitution value if there is an error condition or the measurement value is below lower limit (LL) or upper limit (UL). By default it is the largest 32 bit positive integer.

SSI resolution

Available resoltion modes:

SSI configuration – resolution
Value	Resolution
0x00 (0)	100 nm
0x01 (1)	500 nm
0x02 (2)	1 μm
0x03 (3)	2 μm
0x04 (4)	5 μm
0x05 (5)	10 μm
0x06 (6)	20 μm
0x07 (7)	40 μm
0x08 (8)	50 μm
0x09 (9)	100 μm

SSI offset

This parameter is an optional offset value for the main data.

Note

The offset is used for the following data only:

Position of the first position magnet
Position difference

The offset for all the other data is ignored.

SSI additional data enable

Enables the additional data that follows immediately the main data.

SSI additional data selector

SSI additional data selector – options
Value	Meaning
0x01 (1)	Postition of the second position magnet
0x02 (2)	Velocity of the first position magnet (signed)
0x03 (3)	Velocity of the first position magnet (absolute)
0x04 (4)	Position difference
0x10 (16)	Internal temperature
0x11 (17)	Movement distance
0x12 (18)	Device operating time
0x80 (128)	Multiplexer data

Note

If Multiplexer data option is enabled, the state of the two digital inputs determines which value is set as additional data. Not all variant supports this mode.

Note

The unit for Movement distance and Device operating time depends on the number of bits used for the additional data.

For more information, see Additional data and multiplexer input section.

SSI additional data configuration

Invert

This parameter reverses the output characteristic curve.

Note

Invert is only available for position data.

Number of bits

This field specifies how many bits are used to represent the additional data.

Only the following options are available:

SSI additional data configuration – number of bits
Value	Meaning
0x08 (8)	8 bit
0x10 (16)	16 bit
0x18 (24)	24 bit

Note

The following values are not available in 8 bit mode:

Position of the second magnet
Velocity of the first position magnet (signed)
Velocity of the first position magnet (absolute)
Position difference

The following values are not available in 24 bit mode:

Internal temperature
Movement distance
Device operating hours
Multiplexer data

Hysteresis

This parameter specifies the position or velocity hysteresis. The unit is μm (position data) or 0.1 mm/s (velocity data). The value must be between 0 and 10.000 (inclusive), see Hysteresis.

Error value

This parameter defines the substitution value when an error condition occurs. By default, it is the largest 32 bit positive integer.

SSI additional data resolution

This parameter controls the additional data resolution. See SSI resolution for available options.

Note

This parameter controls the resolution for the following additional data:

Position of the second position magnet
Position difference

The resolution for all the other additional data modes is fixed.

SSI additional data offset

This parameter is an optional offset value for the additional data.

Note

The offset is used for the following data only:

Position of the second position magnet
Position difference

The offset for all the other data is ignored.

Additional data and multiplexer input

In case of Movement distance and Device operating time the unit depends on the SSI additional data configuration - Number of bits field.

Movement distance - unit
Number of bits	Unit
0x08 (8)	1000 km
0x10 (16)	km

Device operating time - unit
Number of bits	Unit
0x08 (8)	1000 hours
0x10 (16)	24 hours (day)

The unit for Internal temperature is °C.

When the additional data selector is set to Multiplexer input, the two digital inputs of the BTL selects between the following additional data values:

Multiplexer input
La	Lb	Meaning
LOW (0)	LOW (0)	Additional data disabled
LOW (0)	HIGH (1)	Internal temperature
HIGH (1)	LOW (0)	Movement distance
HIGH (1)	HIGH (1)	Device operating time