MCMC68HC05L16 Freescale Semiconductor, Inc, MCMC68HC05L16 Datasheet - Page 99

• Manufacturer Part Number: MCMC68HC05L16
• Description: M68hc05 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

10.3 Backplane Driver and Port Selection
The number of backplane (port D) pins depends on the LCD duty. It is automatically selected by DUTY1
and DUTY0 bits in the LCD control register (LCDCR). On reset, these bits are cleared and 1/4 duty is
selected. (See
10.4 Frontplane Driver and Port Selection
The number of frontplane (FP) pins depends on the number of port D and port E bits. If port bits are
selected as a parallel output port, the number of the FP pins is decreased to 27 as a minimum. The
selections between frontplane and port (nibble wide) are done by the PEH, PEL, and PDH bits in the
LCDCR (see
PEMUX registers. PDH, PEH, and PEL have priority over the mux registers. On reset, port D and port E
bits are disconnected and FP27–FP38 pins output V
Freescale Semiconductor
Table
PEH
Table
0
0
1
Duty
1 / 1
1 / 2
1 / 3
1 / 4
10-2). These bits also can be controlled on a bit-wide basis by using the PDMUX and
PEL
10-1.)
0
0
1
FP / Port Control
DUTY1
PDH
MC68HC05L16 • MC68HC705L16 Data Sheet, Rev. 4.1
0
1
1
0
0
0
1
LCD Control
Table 10-2. Frontplane and Port Selection
Table 10-1. Backplane and Port Selection
PDMx
X
X
0
1
1
DUTY0
1
0
1
0
PEMx
X
X
0
1
0
1
BP3/PD3
PD3
PD3
PD3
BP3
FP27:FP30/
FP27:FP30
DD
PE7:PE4
PE7:PE4
Varied
levels.
BP2/PD2
PD2
PD2
BP2
BP2
Pin Selection
Port Selection
FP31:FP34/
FP31:FP34
PE3:PE0
PE3:PE0
Varied
BP1/PD1
Backplane Driver and Port Selection
PD1
BP1
BP1
BP1
FP35:FP38/
FP35:FP38
PD7:PD4
PD7:PD4
Varied
BP0
BP0
BP0
BP0
BP0
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