UPD78F0838 Renesas Electronics Corporation., UPD78F0838 Datasheet - Page 699

• Manufacturer Part Number: UPD78F0838
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

(2)
Segment signals
(a)
(b)
(c)
(d)
Check, with the information given above, what combination of front-surface electrodes (corresponding to the
segment signals) and rear-surface electrodes (corresponding to the common signals) forms display patterns
in the LCD display data memory, and write the bit data that corresponds to the desired display pattern on a
one-to-one basis.
LCD display data memory bits 1 to 3, and bit 3 are not used for LCD display in the static display, three-time
slot modes, respectively. So these bits can be used for purposes other than display.
The higher 4 bits of “F9D0H to F9D3H” are fixed to 0.
The segment signals correspond to 40 bytes of the LCD display data memory (F9D0H to F9F7H) during
an LCD display period, bits 0, 1, 2, and 3 of each byte are read in synchronization with COM0, COM1,
COM2, and COM3, respectively. If a bit is 1, it is converted to the select voltage, and if it is 0, it is
converted to the deselect voltage. The conversion results are output to the segment pins (SEG0 to
SEG39).
The segment signals correspond to 32 bytes of the LCD display data memory (F9D0H to F9EFH) during
an LCD display period, bits 0, 1, 2, and 3 of each byte are read in synchronization with COM0, COM1,
COM2, and COM3, respectively. If a bit is 1, it is converted to the select voltage, and if it is 0, it is
converted to the deselect voltage. The conversion results are output to the segment pins (SEG0 to
SEG31).
The segment signals correspond to 28 bytes of the LCD display data memory (F9D0H to F9EBH) during
an LCD display period, bits 0, 1, 2, and 3 of each byte are read in synchronization with COM0, COM1,
COM2, and COM3, respectively. If a bit is 1, it is converted to the select voltage, and if it is 0, it is
converted to the deselect voltage. The conversion results are output to the segment pins (SEG0 to
SEG27).
The segment signals correspond to 24 bytes of the LCD display data memory (F9D0H to F9E7H) during
an LCD display period, bits 0, 1, 2, and 3 of each byte are read in synchronization with COM0, COM1,
COM2, and COM3, respectively. If a bit is 1, it is converted to the select voltage, and if it is 0, it is
converted to the deselect voltage. The conversion results are output to the segment pins (SEG0 to
SEG23).
PD78F0838, 78F0839
PD78F0840, 78F0841, 78F0846, 78F0847
PD78F0842, 78F0843, 78F0848, 78F0849
PD78F0836, 78F0837, 78F0844, 78F0845
CHAPTER 17 LCD CONTROLLER/DRIVER
Preliminary User’s Manual U19748EJ1V0UD
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