FEATURES
Memory – – – 512 × 4-bit RAM 8 K × 8-bit ROM (S3C7238/P7238) 16 K × 8-bit ROM (S3C7235/P7235) Bit Sequential Carrier – Support 16-bit serial data transfer in arbitrary format Interrupts – – – Three internal vectored interrupts Three external vectored interrupts Two quasi-interrupts I/O Pins – – – Input only: 8 pins I/O: 24 pins Output: 8 pins sharing with segment driver outputs Memory-Mapped I/O Structure – Data memory bank 15 LCD Controller/Driver – – – Maximum 16-digit LCD direct drive capability 32 segment, 4 common pins Display modes: Static, 1/2 duty (1/2 bias), 1/3 duty (1/2 or 1/3 bias), 1/4 duty (1/3 bias) Two Power-Down Modes – – Idle mode (only CPU clock stops) Stop mode (main or sub system oscillation stops) 8-Bit Basic Timer – – Programmable interval timer Watchdog timer Oscillation Sources – – – – – Crystal, ceramic, or RC for main system clock Crystal or external oscillator for subsystem clock Main system clock frequency: 4.19 MHz (typical) Subsystem clock freque...
Samsung semiconductor
