LC876764A/48A

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Features

(1) Read-Only Memory (ROM): LC876764A 65536 × 8 bits

LC876748A

49152 × 8 bits

(2) Random Access Memory (RAM): LC876764A/48A

1536 × 9 bits

(3) Minimum Bus Cycle Time: 100ns (10MHz)

Note: The bus cycle time indicates ROM read time.

(4) Minimum Instruction Cycle Time: 300ns (10MHz)

(5) Ports

- Input/output ports

Data direction programmable for each bit individually :

20 (P1n, P70 to P73, P8n)

- 15V withstand input/output ports

Data direction programmable in nibble units :

8 (P0n)

(When N-channel open drain output is selected, data can be input in bit units.)

Data direction programmable for each bit individually :

8 (P3n)

- Input ports :

2 (XT1,XT2)

- VFD output ports

Large current outputs for digits :

9 (S0 / T0 to S8 / T8)

Large current outputs for digits / segments :

7 (S9 / T9 to S15 / T15)

digit / segment outputs :

8 (S16 to S23)

segment outputs :

28 (S24 to S51)

Other functions

Input/output ports :

12(PFn, PG0 to 3)

Input ports :

24 (PCn, PDn, PEn)

- Oscillator pins :

2 (CF1,CF2)

- Reset pin :

1 (RES#)

- Power supply :

6 (VSS1 to 2, VDD1 to 4)

(6) VFD automatic display controller

- Programmable segment/digit output pattern

Output can be switched between digit/segment waveform output (pins 9 to 24 can be used for

output of digit waveforms).

parallel-drive available for large current VFD.

- 16-step dimmer function available

(7) Weak signal detection (MIC signals etc)

- Counts pulses with width greater than a preset value

- 2 bit counter

(8) Timers

- Timer 0: 16 bit timer / counter with capture register

Mode 0: 2 channel 8-bit timer with programmable 8 bit prescaler and 8 bit capture register

Mode 1: 8 bit timer with 8 bit programmable prescaler and 8 bit capture register + 8 bit

Counter with 8-bit capture register

Mode 2: 16 bit timer with 8 bit programmable prescaler and 16 bit capture register

Mode 3: 16 bit counter with 16 bit capture register