CY545 Stepper System Controller
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the amount of memory required for your program. Before running the program, the Y command
should be used to redefine the pointer value for the start of the program.
Note that the carriage return character is optional after the Quit command in the ASCII
command mode, and a data count is not used after the Quit command in the Binary command
mode.
Running From External Memory
Two commands are involved in running programs from the external memory. They are:
X
0
Execute external memory commands
Stop external memory command execution
The Execute command changes the CY545 from the direct command mode to the program
execution mode. Your program will begin running from external memory, at the current address
in the address pointer. The X command would normally be preceded by a Y command to set the
program starting address.
In the program execution mode, the CY545 will begin reading command characters from the
memory, incrementing the address pointer after every read operation. When an entire command
has been read into the part, that command is executed similarly to directly issued commands.
When the current command is finished, the CY545 will read the next command from memory
and execute it. This process continues until the CY545 finds a stop command.
The Zero command (ASCII character 0, not binary value zero) is the stop execution command.
When this command is executed, the CY545 changes from program execution mode back to
direct command mode. It then waits for the next command to be issued by the host system.
Note that in the Binary command mode, the binary value zero should be used for the stop
execution command, followed by a zero value data count.
© 2002 Cybernetic Micro Systems
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Chapter 7 - External Memory Commands
ETC [ ETC ]
