NEC mPD780852 Series, Preliminary User'S Manual

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CHAPTER 18 METER CONTROLLER/DRIVER
Preliminary User’s Manual U14581EJ3V0UM00
(3) Port mode control register (PMC)
PMC is an 8-bit register that specifies PWM/port output.
PMC is set with an 8-bit memory manipulation instruction.
RESET input clears PMC to 00H.
Figure 18-5 shows the PMC format.
Figure 18-5. Port Mode Control Register (PMC) Format
Address: FF6AH After Reset: 00H R/W
Symbol 7 6 5 4 3 2 1 0
PMC MOD4 MOD3 MOD2 MOD1 EN4 EN3 EN2 EN1
MODn Meter n Full/Half Bridge Selection
0 Meter n output is full bridge.
1 Meter n output is half bridge.
ENn Meter n Port/PWM Mode Selection
0 Meter n output is in port mode.
1 Meter n output is in PWM mode.
Remark n = 1 to 4
The relation among the ENn and MODn of the PMC register, DIRn1 and DIRn0 of the MCMPCn register, and
output pins is shown below.
ENn MODn DIRn1 DIRn0 SMn1 SMn2 SMn3 SMn4 Mode
(sin+) (sin–) (cos+) (cos–)
0
× × ×
Port Port Port Port Port mode
1 0 0 0 PWM 0 PWM 0 PWM mode full bridge
1 0 0 1 PWM 0 0 PWM
1 0 1 0 0 PWM 0 PWM
1 0 1 1 0 PWM PWM 0
1 1 0 0 PWM Port PWM Port PWM mode half bridge
1 1 0 1 PWM Port Port PWM
1 1 1 0 Port PWM Port PWM
1 1 1 1 Port PWM PWM Port
DIRn1 and DIRn0 mean the quadrant of sin and cos. DIRn1 and DIRn0 = 00 through 11 correspond to quadrants
1 through 4, respectively. The PWM signal is output to the specific pin of the + and – polarities of sin and cos
of each quadrant.
When ENn = 0, all the output pins are used as port pins regardless of MODn, DIRn1, and DIRn0.
When ENn = 1 and MODn = 0, the full bridge mode is set, and 0 is output to a pin that does not output a PWM
signal.
When ENn = 1 and MODn = 1, the half bridge mode is set, and the pin that does not output a PWM signal is
used as a port pin.
Caution The output polarity of the PWM output changes when MCNT overflows.