The PIC16LC505T-04/SL is the controller, which uses microchip technology and is a low-cost, high-performance, 8-bit, fully static, EPROM/rom-based CMOS microcontroller. It uses a RISC architecture with only 33 words/single loop instruction. All instructions are single cycle (200µs) except for program branches, which take two cycles.

The controller PIC16LC505T-04/SL outperforms its competitors by an order of magnitude. 12-bit wide instructions are highly symmetrical, resulting in typical 2:1 code compression over other 8-bit microcontrollers in their class. The easy-to-use and easy-to-remember instruction set greatly reduces development time.

The controller PIC16LC505T-04/SL product has special features that reduce system cost and power requirements. Power-on reset (POR) and device reset timer (DRT) eliminate the need for external reset circuitry. There are five mode shapes to choose from, including the INTRC internal mode shape and the power saving low voltage (low power consumption) mode shape. Power saving sleep mode, watchdog timer and code protection functions improve system cost, power and reliability.

The PIC16C505 is a cost-effective one-time programmable (OTP) version suitable for any volume production. Customers can take advantage of Microchip's price leadership in OTP microcontrollers, while taking advantage of the flexibility of OTP.

The PIC16C505 product is supported by a full-featured macro assembler, a software simulator, an in-circuit simulator, a "C" compiler, a low-cost development programmer and a full-featured programmer. All tools support IBM PCs and compatible machines.

1.1 Applications

The PIC16C505 is suitable for a variety of applications from personal care equipment and security systems to low power remote transmitter/receivers. EPROM technology makes customizing applications (transmitter code, device settings, receiver frequencies, etc.) extremely fast and convenient. The small footprint package, through hole or surface mount, makes this microcontroller perfect for applications with space constraints. Low cost, low power, high performance, ease of use and I/O flexibility enable the PIC16C505 to be used even in areas where microcontrollers were not previously considered (eg timer functions, replacement of "glue" logic in larger systems and PLD logic and coprocessor applications) are also very versatile

In the controller PIC16LC505T-04/SL, the DRT runs as long as the device is powered on. The DRT operates from reset and varies based on oscillator selection and reset type (see Table 7-5).

The DRT operates on an internal RC oscillator. The processor remains in reset as long as the DRT is active. The DRT delay allows VDD to exceed the VDD minimum and allow the oscillator to stabilize.

The time delay for device reset will vary from chip to chip due to VDD, temperature and process variations. See AC parameters for details.

DRT also triggers when the watchdog times out. This is especially important for applications that use the WDT to automatically wake from sleep mode.

The reset sources are POR, MCLR, WDT timeout and pin change wake-up.