Delta Tau GEO BRICK LV User Manual
Turbo PMAC User Manual
136
Motor Compensation Tables and Constants
Conversion Table Execution
The conversion table executes automatically at the beginning of each servo cycle, immediately after the
servo interrupt. The entire active part of the table executes before any servo loops execute that cycle.
Each entry in the table is executed every servo interrupt, even if the result is used less often (as when a
motor’s own servo cycle is extended with Ixx60) or not at all.
servo interrupt. The entire active part of the table executes before any servo loops execute that cycle.
Each entry in the table is executed every servo interrupt, even if the result is used less often (as when a
motor’s own servo cycle is extended with Ixx60) or not at all.
The table is executed in order from top to bottom each cycle. If the result of one entry is used as the
source for another entry, usually it is desirable to have the second entry further down in the table, so a
servo cycle’s delay is not introduced.
source for another entry, usually it is desirable to have the second entry further down in the table, so a
servo cycle’s delay is not introduced.
Conversion Table Structure
The Encoder Conversion Table has two columns, one in the X memory space of the processor, and one in
the Y memory space. The X-column holds the converted data, while the Y-column holds the addresses of
the source registers, and the conversion methods used on the data in each of those source registers.
Basically, you set up the table by writing to the Y-column, and PMAC uses the Y-column data to fill up
the X-column each servo cycle.
the Y memory space. The X-column holds the converted data, while the Y-column holds the addresses of
the source registers, and the conversion methods used on the data in each of those source registers.
Basically, you set up the table by writing to the Y-column, and PMAC uses the Y-column data to fill up
the X-column each servo cycle.
The table is a series of entries, each of which produces one final result value. Each entry can be 1, 2, or 3
lines (rows) long, with both setup and result data in each line. The final result of the entry is in the last
data line. The entire table is 192 lines long, although typically not all lines are used in a given
application.
lines (rows) long, with both setup and result data in each line. The final result of the entry is in the last
data line. The entire table is 192 lines long, although typically not all lines are used in a given
application.
Turbo PMAC Encoder Conversion Table
X-Memory
Y-Memory
(Results)
(Set-up)
1. Single Line Entry
Bits Bits
Bits Bits
5-23 0-4
20-23,
19 0-18
Result: Integer
Fraction
Method, mode bit
Source Address
2. Multi-Line Entry
Bits Bits
Bits Bits
5-23 0-4
20-23,
19 0-18
(Intermediate Result)
Method, mode bit
Source Address
• • •
(Conversion
Factors)
Result: Integer
Fraction
• • •
Setup Structure
Each setup line is represented by an I-variable. The first setup line of the table is represented by I8000,
the second by I8001, and so on; the last setup line of the table is represented by I8191. Because
individual entries are 1, 2, or 3 lines long, each entry uses 1, 2, or 3 setup I-variables, consecutively
numbered.
the second by I8001, and so on; the last setup line of the table is represented by I8191. Because
individual entries are 1, 2, or 3 lines long, each entry uses 1, 2, or 3 setup I-variables, consecutively
numbered.
These I-variables are 24-bit unsigned variables, usually represented as 6-digit hexadecimal values; they
are reported as hexadecimal values if I9 is set to the default of 2, or to 3. Detailed descriptions of the
values these I-variables can take are given in the Software Reference Manual description of I-variables
I8000 – I8191.
are reported as hexadecimal values if I9 is set to the default of 2, or to 3. Detailed descriptions of the
values these I-variables can take are given in the Software Reference Manual description of I-variables
I8000 – I8191.