Delta Tau GEO BRICK LV User Manual
Turbo PMAC User Manual
Motor Compensation Tables and Constants
143
Examples:
I8000=$F78200
; Hi-res interpolation of Servo IC 2 Channel 1 (PMAC1 IC)
I8001=$078202
; Read ADCs from Servo IC 2 Channel 1
I8002=$004000
; Bias term of 4 LSBs of 12-bit ADCs
I8000=$FF8300
; Hi-res interpolation of Servo IC 3 Channel 1 (PMAC2 IC)
I8001=$078305
; Read ADCs from Servo IC 3 Channel 1
I8002=$000000
; Zero bias term
Acc-28 Analog-to-Digital Converters
The conversion table can process the data from the 16-bit A/D converters of Acc-28 boards or their
equivalent. The source address is that of the A/D converter register in the IC that interfaces to the accessory.
equivalent. The source address is that of the A/D converter register in the IC that interfaces to the accessory.
Standard A/D conversion (Method digit $1)
This method takes the value in the A/D converter (without integrating it) and shifts it to leave the LSB in
bit 5 of the result – what Turbo PMAC software considers a count. If the A/D converter provides a
signed value (Acc-28A), the mode-switch bit should be set to 0; if the A/D converter provides an
unsigned value (Acc-28B, 28E), the mode-switch bit should be set to 1. This is a single-line entry.
Common source addresses are:
Acc-28A/B into PMAC channel 1 – 4: $78006, $78007, $7800E, $7800F
Acc-28B into PMAC2 channel 1A, 1B, 2A, 2B: $78005, $78006, $7800D, $7800E
Acc-28E as first I/O board, channel 1 – 4: $78C00, $78C01, $78C02, $78C03
Examples:
bit 5 of the result – what Turbo PMAC software considers a count. If the A/D converter provides a
signed value (Acc-28A), the mode-switch bit should be set to 0; if the A/D converter provides an
unsigned value (Acc-28B, 28E), the mode-switch bit should be set to 1. This is a single-line entry.
Common source addresses are:
Acc-28A/B into PMAC channel 1 – 4: $78006, $78007, $7800E, $7800F
Acc-28B into PMAC2 channel 1A, 1B, 2A, 2B: $78005, $78006, $7800D, $7800E
Acc-28E as first I/O board, channel 1 – 4: $78C00, $78C01, $78C02, $78C03
Examples:
I8004=$178006
; Conversion of Servo IC 0 ADC 1 (PMAC1 IC), signed
I8005=$1F8105
; Conversion of Servo IC 1 ADC 1A (PMAC2 IC), unsigned
I8006=$1F8C00
; Conversion of first Acc-28E Channel 1, unsigned
Integrated A/D conversion (Method digit $5)
This method takes the value in the A/D converter, shifts it so the LSB is in bit 5 and adds it to the
previous cycle’s result to yield a numeric integration. If the A/D converter provides a signed value (Acc-
28A), the mode-switch bit should be set to 0; if the A/D converter provides an unsigned value (Acc-28B,
28E), the mode-switch bit should be set to 1. This is a double-line entry. The second line holds a bias
term, expressed as a 24-bit number, that is subtracted from the source A/D data (whose LSB is in bit 8)
before the numerical integration.
Examples:
previous cycle’s result to yield a numeric integration. If the A/D converter provides a signed value (Acc-
28A), the mode-switch bit should be set to 0; if the A/D converter provides an unsigned value (Acc-28B,
28E), the mode-switch bit should be set to 1. This is a double-line entry. The second line holds a bias
term, expressed as a 24-bit number, that is subtracted from the source A/D data (whose LSB is in bit 8)
before the numerical integration.
Examples:
I8004=$578006
; Integration of Servo IC 0 ADC 1 (PMAC1 IC), signed
I8005=$000300
; Bias term (3 LSBs of 16-bit ADC)
Parallel Feedback
The conversion table can process parallel feedback data read from a register or set of registers. While this
is fundamentally a copying operation, it serves several important functions:
is fundamentally a copying operation, it serves several important functions:
•
It copies the data into an X-register, where the servo-loop I-variables can access it (most I/O
registers are in Y-memory).
registers are in Y-memory).
•
It can shift the data so the LSB of the source register ends in bit 5 of the result, which PMAC
firmware treats as a count.
firmware treats as a count.
•
It can mask out unwanted bits from the source word, and properly handle rollover and software
extension.
extension.
•
It can perform a filtering function, mitigating the effect of noise in significant data bits.
Parallel feedback data can be read from a continuous range of bits up to 24-bits wide from within a 48-bit
range, or from 2 or 3 byte-wide pieces in consecutive registers, as from many of the UMAC I/O boards.
Five method digits for the first setup line of the entry in the conversion table handle this case:
range, or from 2 or 3 byte-wide pieces in consecutive registers, as from many of the UMAC I/O boards.
Five method digits for the first setup line of the entry in the conversion table handle this case: