Reference Manual

PMAC 2 Software Reference
PMAC I-Variable Specification 43
For the ACC-36 board automatically converted using I60 and I61, the board must never be
accessed in user programs, but user programs may read the memory registers in PMAC to
which the ADC values are copied.
If I60 is set to 0, no automatic conversion will take place. If the first two hex digits of I60
are set to anything except $FF, PMAC will automatically change them to $FF.
ADCs 1 to 8 are copied into the low 12 bits of registers Y:$0708 to Y:$070F, respectively.
ADCs 9 to 16, if they exist on the addressed board, are copied into the low 12 bits of
registers X:$0708 to X:$070F. These registers should be treated as signed registers.
Note:
It is easier to specify this parameter in hexadecimal form ($ prefix).
If I9 is set to 2 or 3, the value of this variable will be reported back
to the host in hexadecimal form.
Example
A PMAC system has an ACC-14D at address $FFD0, and an ACC-36 at address $FFD8.
It is desired to automatically convert all 8 registers on the ACC-36. I60 is set to $FFD8,
and I61 is set to 7.
See Also
Parallel Position Feedback Conversion (Setting Up a Motor)
I-variables I61, Ix10
Memory and I/O Map registers $FFD0 to $FFFE
ACC-36 User’s Manual
I61 Number of Auto-Converted ADC Registers {PMAC(1) only}
Range
0 .. 7
Units
Number of registers minus 1
Default
0
Remarks
I61 permits the user to specify the number of analog-to-digital converter (ADC) registers
on the ACC-36 specified by I60 that will be automatically converted and copied into
PMAC(1) memory. There are two 12-bit converters per 24-bit register. The number of
registers converted automatically is equal to I61 + 1.
On a PMAC2 board, this function is controlled by the more flexible structure of the analog
data table.
Each phase cycle (9 kHz default), PMAC copies the contents of an ACC-36 register into
RAM, then selects the next register, so the conversion can start and the results will be
ready for the next phase cycle. PMAC will cycle through the first I61+1 registers on the
ACC-36 in this fashion. If I61 is set to 0, PMAC will cycle through all 8 registers on the
ACC-36 (equivalent to I61=7).
If you have more than one ACC-36 connected to PMAC, only one board may be used in
this manner. All other boards must be accessed in user programs. For the ACC-36 board
automatically converted using I60 and I61, the board must never be accessed in user
programs, but user programs may read the memory registers in PMAC to which the ADC
values are copied.
ADCs 1 to 8 are copied into the low 12 bits of registers Y:$0708 to Y:$070F, respectively.
ADCs 9 to 16 are copied into the low 12 bits of registers X:$0708 to X:$070F. These
registers should be treated as signed values.
Example
The system has 8 axes with analog feedback. There are 4 phase cycles per servo cycle,