NPM Motionnet G9001A, User Manual

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DA70131-1/3E
IV-22
In all, the following operations were commanded by the CPU emulation device.
1st process: Write 0100h to the specified address (004h).
2nd process: Write 0000h to the specified address (006h).
Actually, these operations are equivalent to the procedures used to place data in the I/O buffer of the PCL6045B.
After that, instructions are needed about which data should be written to which register.
These are equivalent to the following blocks written to the FIFO. Let's look at them.
0100h and 0081h were written to the FIFO.
The first data is sent to the CPU emulation device. The interpreted meanings are as follows.
[Interpreted results] Write data (0081h) to specified address (00h) once.
This instruction is used to issue a command to the PCL6045B and has the meaning: write the contents of the I/O
buffer into the PRFL register
Now the data are sent to the PRFL.
In the same way, commands can be stacked up in the FIFO, so that the register setting is complete.
The last "0100h" and "0051h" mean: write 0051h to address 00h.
This instruction corresponds to the FH speed start command on the PCL6045B. After receiving this instruction, the
PCL6045B starts feeding pulses at FH speed.
Groups of commands can be stacked up for sending in the FIFO. When a certain number of commands is stored in
the FIFO, send the command data to the CPU emulation device using data communication.
While interpreting the command data received, the CPU emulation device will repeat its operation as a substitute
for a CPU.
When all of the commands have been received, the CPU emulation device turns on a bit in the status data which
mean that the local side has completed the reception process. This is passed along to the center device (by cyclic
communication).
Notes
Be careful about the size of the command data group sent to the CPU emulation device.
The FIFO in the center device is 256 bytes long. As long as the command group size does not exceed this value,
there should not be a problem.
However, if the communication data increases, the ratio of data that need to be caught as communication errors,
such as electrical noise, will increase. If the amount of data is small, the data packet size used for sending is also
small, and it may be possible to for data packets to pass through between burst of noise. If the packet size is too
large, a data collapse may occur due to a noise environment (CRC error), in which case proper communication
cannot be established.
If the communication line is too long or the number of local devices connected is too great, it is better to send
command data after dividing it into smaller pieces.