CY545 Stepper System Controller
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© 2002 Cybernetic Micro Systems
Chapter 4 - Command Summary
17
Binary Command Format
The Binary format still starts with the ASCII command letter for each command. However, the
format for parameters is quite different in Binary mode. The command letter is always followed
immediately by a binary data count, representing the number of data bytes needed by the
command. For commands without parameters, such as the Go command, the data count is a
binary value zero (not the ASCII character “0"). For commands with parameters, the data count
represents the number of bytes needed to specify the parameter(s). This byte count must match
the expected size of the parameters. For example, the Number command must always have a
data count of three, for its 24-bit parameter, even if the most significant byte values are zero.
The Quit command, which ends the entry of commands into external memory, should not be
followed by any data count. This command is immediately followed by the ASCII letter of the
next desired command. Also, the Stop command must use the binary value zero, not the ASCII
character “0", followed by a data count which is also zero.
All multi-byte parameters must be entered least significant byte first. For example, the Zloop
command has a 16-bit count, followed by an 8-bit address, so it has a data count of three, with
the data byte sequence being the LSByte of the count, the MSByte of the count, then the branch
address. More examples are shown below. The data bytes are shown as hex values, with a
space separating each one for clarity, but they are issued to the CY545 as single 8 bit values,
without the spaces.
G 00
No argument, byte count zero
R 01 87
Single byte argument
D 02 3B 1A
Two byte argument, value 1A3BH
N 03 11 22 33
Three byte argument, value 332211H
Z 03 21 04 92
Multiple arguments, Z 0421H,92H
The following sections describe each of the CY545 commands. The commands have been
organized into groups of related functions.