AT89S51 8-Bit Microcontroller PDIP-40
Low-power, high-performance CMOS 8-bit AT89S51 microcontroller with 4KB of ISP flash memory. The device uses Microchip high-density, nonvolatile memory technology and is compatible with the industry-standard 80C51 instruction set and pinout. On-chip flash allows program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer.
Features
- Compatible with MCS®-51 Products
- 4K Bytes of In-System Programmable (ISP) Flash Memory
- Endurance: 1000 Write/Erase Cycles
- 4.0V to 5.5V Operating Range
- Fully Static Operation: 0 Hz to 33 MHz
- Three-level Program Memory Lock
- 128 x 8-bit Internal RAM
- 32 Programmable I/O Lines
- Two 16-bit Timer/Counters
- Six Interrupt Sources
- Full Duplex UART Serial Channel
- Low-power Idle and Power-down Modes
- Interrupt Recovery from Power-down Mode
- Watchdog Timer
- Dual Data Pointer
- Power-off Flag
- Fast Programming Time
- Flexible ISP Programming (Byte and Page Mode)
PINOUT
| Pin | Pin Name | Description |
|---|---|---|
| 1 | P1.0 | Port 1 bit 0 (general-purpose I/O) |
| 2 | P1.1 | Port 1 bit 1 (general-purpose I/O) |
| 3 | P1.2 | Port 1 bit 2 (general-purpose I/O) |
| 4 | P1.3 | Port 1 bit 3 (general-purpose I/O) |
| 5 | P1.4 | Port 1 bit 4 (general-purpose I/O) |
| 6 | P1.5 | Port 1 bit 5 (general-purpose I/O) |
| 7 | P1.6 | Port 1 bit 6 (general-purpose I/O) |
| 8 | P1.7 | Port 1 bit 7 (general-purpose I/O) |
| 9 | RST | Reset input (active high) |
| 10 | P3.0 / RXD | Port 3 bit 0 or UART receive |
| 11 | P3.1 / TXD | Port 3 bit 1 or UART transmit |
| 12 | P3.2 / INT0 | Port 3 bit 2 or external interrupt 0 |
| 13 | P3.3 / INT1 | Port 3 bit 3 or external interrupt 1 |
| 14 | P3.4 / T0 | Port 3 bit 4 or external Timer 0 input |
| 15 | P3.5 / T1 | Port 3 bit 5 or external Timer 1 input |
| 16 | P3.6 / WR | Port 3 bit 6 or external data memory write strobe |
| 17 | P3.7 / RD | Port 3 bit 7 or external data memory read strobe |
| 18 | XTAL2 | Crystal oscillator output |
| 19 | XTAL1 | Crystal oscillator input |
| 20 | GND | Ground (0 V) |
| 21 | P2.0 / A8 | Port 2 bit 0 or Address bit 8 for external memory |
| 22 | P2.1 / A9 | Port 2 bit 1 or Address bit 9 for external memory |
| 23 | P2.2 / A10 | Port 2 bit 2 or Address bit 10 for external memory |
| 24 | P2.3 / A11 | Port 2 bit 3 or Address bit 11 for external memory |
| 25 | P2.4 / A12 | Port 2 bit 4 or Address bit 12 for external memory |
| 26 | P2.5 / A13 | Port 2 bit 5 or Address bit 13 for external memory |
| 27 | P2.6 / A14 | Port 2 bit 6 or Address bit 14 for external memory |
| 28 | P2.7 / A15 | Port 2 bit 7 or Address bit 15 for external memory |
| 29 | PSEN | Program Store Enable — for external program memory read |
| 30 | ALE / PROG | Address Latch Enable or Program pulse input |
| 31 | EA / VPP | External Access Enable / Programming voltage input |
| 32 | P0.7 / AD7 | Port 0 bit 7 or Address/Data bit 7 when external memory accessed |
| 33 | P0.6 / AD6 | Port 0 bit 6 or Address/Data bit 6 when external memory accessed |
| 34 | P0.5 / AD5 | Port 0 bit 5 or Address/Data bit 5 when external memory accessed |
| 35 | P0.4 / AD4 | Port 0 bit 4 or Address/Data bit 4 when external memory accessed |
| 36 | P0.3 / AD3 | Port 0 bit 3 or Address/Data bit 3 when external memory accessed |
| 37 | P0.2 / AD2 | Port 0 bit 2 or Address/Data bit 2 when external memory accessed |
| 38 | P0.1 / AD1 | Port 0 bit 1 or Address/Data bit 1 when external memory accessed |
| 39 | P0.0 / AD0 | Port 0 bit 0 or Address/Data bit 0 when external memory accessed |
| 40 | VCC | Positive supply voltage (typically +5 V) |
Specifications
| Attribute | Value |
| RAM Size | 128Byte |
| Program FLASH Size | 4K@x8bit |
| Operating Temperature Range | -40℃~+85℃ |
| Supply Voltage Range | 4V~5.5V |
| CPU Core | 51Series |
| Peripherals / Functions / Protocol Stacks | WDT |
| Internal Oscillator | Internal oscillator included |
| Maximum Frequency | 24MHz |
| GPIO Ports Number | 32 |
