Appendix B: MCX312 Registers
This part gives the users some refereces about how to access the registers in the MCX312
chip. For more details, users still have to refer to this chip’s manual provided by NOVA
electronics Inc..
B.1 Command Register: WR0
Command register is used for the axis assignment and command
registration for each axis in MCX312. The register consists of the bit for axis
assignment, bit for setting command code, and bit for command resetting.
After the axis assignment and command code have been written to the
register, this command will be executed immediately. The data such as drive
speed setting and data writing command must be written to registers WR6 and
WR7 first. Otherwise, when the reading command is engaged, the data will be
written and set, through IC internal circuit, to registers RR6 and RR7.
When using the 8-bit data bus, the user should write data into the high word byte
(H), then low word byte (L).
It requires 250 nSEC (maximum) to access the command code when
CLK=16MHz. The input signal BUSYN is on the Low level at this moment. Please
don’ t write the next command into WR0 before BUSYN return to the Hi level.
WR0
Axis Assignment
Command Code
D5 ~ 0 Command code setting Please refer to chapter 5 and the chapters
following for further description of command codes.
D9 ~ 8 Axis assignment When the bits of the axis are set to 1, the axis is
assigned. The assignment is not limited only for one axis, but for multi-axes
simultaneously. It is possible to write the same parameters also. However, the
data reading is only for one assigned axis. Whenever the interpolation is
commanded, the bits of the assigned axis (axes) should be set 0.
D15 RESET IC command resetting When this bit is set to 1, but others are 0, the
IC will be reset after command writing. After command writing, the BUSYN signal
will be on the Low level within 875 nSEC (When CLK=16 MHz) maximum.
When 8-bit data bus is used, the reset is activated when the command (80h) is
written to register WR0H.
RESET bit should be set to 0 when the other commands are written.
