This is a user's manual for the C501 8-bit single-chip microcontroller.
This manual describes the C501 family of 8‑bit single‑chip microcontrollers, including the C501‑L, C501‑1R and C501‑1E variants. It covers pin configuration, CPU timing, memory maps, on‑chip peripherals such as timers, serial interface, interrupt system and power‑saving modes, as well as OTP memory programming for the C501‑1E version.
The document also lists the device specifications, absolute maximum ratings, DC/AC characteristics, package outlines and provides an index for quick reference. It is intended for engineers designing typical 8051‑compatible applications using the C501 microcontroller.
| Compatibility | Fully compatible with standard 8051 microcontroller |
|---|---|
| Operating Frequency | 12 MHz, 24 MHz, 40 MHz |
| On‑chip ROM (C501‑1R) | 8 KB × 8‑bit |
| On‑chip OTP Memory (C501‑1E) | 8 KB × 8‑bit |
| Data RAM | 256 bytes × 8‑bit |
| I/O Ports | Four 8‑bit ports |
| Timers/Counters | Three 16‑bit timers/counters (timer 2 with up/down feature) |
| Interrupt Sources | Six sources, two priority levels |
| Package Types | P‑DIP‑40, P‑LCC‑44, P‑MQFP‑44 |
| Operating Temperature Range | -40 °C to 85 °C |
The C501 is offered in versions that run at 12 MHz, 24 MHz, or 40 MHz.
The C501‑1R version includes 8 KB of 8‑bit ROM.
The C501‑1E contains 8 KB of one‑time programmable (OTP) memory.
The device provides six interrupt sources with two priority levels.