HC05RC16GRSSLASHD datasheet(23/122 Pages) NXP

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General Description

Signal Description

MC68HC05RC16 — Rev. 3.0

General Release Specification

General Description

1.5.1 VDD and VSS

Power is supplied to the microcontroller’s digital circuits using these two

pins. V

DD is the positive supply and VSS is ground.

1.5.2 IRQ (Maskable Interrupt Request)

In addition to suppling the EPROM with the required programming

voltage, this pin has a mask option as specified by the user that provides

one of two different choices of interrupt triggering sensitivity. The options

are:

1. Negative edge-sensitive triggering only

2. Both negative edge-sensitive and level-sensitive triggering.

The MCU completes the current instruction before it responds to the

interrupt request. When IRQ goes low for at least one t

ILIH (see 11.8

Control Timing (5.0 Vdc and 2.2 Vdc)), a logic 1 is latched internally to

signify that an interrupt has been requested. When the MCU completes

its current instruction, the interrupt latch is tested. If the interrupt latch

contains a logic 1 and the interrupt mask bit (I bit) in the condition code

If the option is selected to include level-sensitive triggering, the IRQ input

requires an external resistor to V

DD for wired-OR operation.

The IRQ pin contains an internal Schmitt trigger as part of its input to

improve noise immunity.

Refer to Section 4. Interrupts for more detail.

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

HC05RC16GRS/D Datasheet(PDF) 23 Page - NXP Semiconductors