CY325 ETC, CY325 Datasheet - Page 106

• Manufacturer Part Number: CY325
• Description: Stepper System Controller
• Manufacturer: ETC

CY545 Stepper System Controller
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Changes from CY545 to CY545A
Please note: the CY545 is obsolete.
The CY545 did not have Clear-to-Send ("CTS"). The CY545A implements CTS function on pin
27.
Changes from CY545A to CY545B
Please note: the CY545A is obsolete.
Added Features:
The CY545A did not allow direct commands during program execution, and entering such
commands caused command fragmentation, or interleaving of the commands from the two
sources. Immediate commands entered at any time during program execution will now be
accepted between executing commands and will be correctly interpreted and executed by the
CY545B.
The CY545B adaptive baud rate can now adapt up to 57,600 baud (@ 11 MHz). While this rate
has always been available as a fixed baud rate, the CY545A was adaptively limited to 300 to
19,200 baud.
The CY545B binary mode now allows ASCII "/" prefix for indicating the complement of a bit
function. The CY545A binary mode required the actual complementary numerical values for
clearing the bits.
The CY545B changes the 5 millisecond time-out at the end of a motion. The time-out value is
now determined by the FirstRate paramenter. Faster rates (higher values) will time out faster
than slow rates. This change affects repetitive single stepping, where a single step (N 1)
command is embedded in a program loop. The CY545A, because of the fixed time-out could
single step continuously at only 200 steps per second (@ 11 MHz), while the CY545B will allow
single stepping at up to approximately 1500 steps per second.
The CY545B tests for a free data bus before writing to the HP Display. This will allow slow
parallel devices time to get off the bus, and so avoid bus conflicts. The CY545A assumed that
parallel devices writing to the bus would do so quickly.
Problems Fixed:
With the CY545A, quoted message strings stored in external memory were not correctly
transferred through the parallel interface, and specifically through the parallel interface to the
CY233. The CY545B corrects this, allowing successful transfer of parallel quoted strings.
© 2002 Cybernetic Micro Systems
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Chapter 20 - Getting Your CY545 Running