User's Manual

PMAC VME Hardware Reference Manual
PMAC Basic Specifications 33
I/O Specifications
Position Feedback
(JMACH1, JMACH2) (Also Acc-24 JMACH3, JMACH4)
Quadrature Encoders
4 (standard) to 16 (depending on options) digital quadrature incremental encoders.
5V TTL or CMOS levels; single-ended or differential.
Sockets provided for termination resistor packs.
Input rate: DC to 19.66 MHz (count rate).
X1, X2, X4 decoding, or pulse and direction.
Digital delay filter for removing noise spikes.
3rd channel input available for position capture.
Unused counters available as timers.
Absolute Encoders
(Thru Accessory-14D I/O Expansion card) (Or other binary parallel-word position
data source)
Up to 12 absolute parallel encoders of 24 bits or less or up to six absolute parallel
encoders of over 24 bits (limit of 6 Acc-14D cards of 48 bits each); straight binary;
5V, single-ended.
Resolvers
(Thru Accessory-8D, Option 7 Resolver-to-Digital Converter card, two or four
resolvers per accessory card).
12-bit resolution; absolute position data read on power-up or reset; thereafter,
simulated quadrature signal is read through incremental encoder input.
Analog Outputs
(JMACH1, JMACH2) (Also Acc-24 JMACH3, JMACH4)
four (standard) to 16 (depending on options) outputs of +/-10V; 16-bit resolution (300
uV/bit), optically isolated; Standard use is for servo output; one per axis if PMAC is
not commutating axis; two per axis if PMAC is commutating axis; uncommitted
analog outputs may be used for other purposes.
On-Board Analog
Input
(JPAN - requires Option 15)
1 input, 0 to +10V, converted to frequency at 25 kHz/V
(On PMAC Lite +/-10V, converted to sign and frequency)
Can be jumpered to Encoder 4 counter; time-base conversion of counter yields 24-bit
register value proportional to voltage. Effective A/D resolution of 10 bits.
Accessory Analog Inputs
(Thru Accessory 28
Analog-to-Digital
Converter Board)
4 to 16 (depending on number) inputs of +/-10V; 16-bit resolution; single-ended or
differential inputs.
Conversion time less than 50 usec, all inputs.
(Thru Accessory 36
Analog-to-Digital
Converter Board)
8 or 16 inputs of 0 to 10V or +/-5V 12-bit resolution per board; single-ended or
differential inputs. Effective conversion time 1 phasing cycle per channel.
Dedicated Axis
Digital Inputs
(JMACH1, JMACH2) (Also Acc-24 JMACH3, JMACH4)
Four dedicated digital inputs accompanying each quadrature encoder; optically
isolated from PMAC digital circuits; operate from +15V voltage source.
Inputs for each encoder are: +LIMIT, -LIMIT, HOME, FAULT.
Uncommitted sets of inputs may be used as general-purpose optically isolated digital
inputs.
Dedicated Axis
Digital Outputs
(JMACH1], JMACH2) (Also Acc-24 JMACH3, JMACH4)
Amplifier Enable
One dedicated digital output accompanying each quadrature encoder; optically
isolated from PMAC digital circuits, operates from +15V voltage source. Serves as
amplifier-enable signal or direction bit; polarity is can be set by hardware jumper
(E17).
Uncommitted lines may be used as general-purpose optically isolated digital outputs.
Position Compare
One dedicated digital output accompanying each quadrature encoder; serves as
position compare output providing pulse exactly when preset count value is reached.
Uncommitted compare outputs may be used as general-purpose outputs by using
polarity control.