CHAPTER 13 MINIMUM HARDWARE CONSIDERATIONS

The 8XC196MC, MD, and MH have several basic requirements for operation within a system. This chapter describes options for providing the basic requirements and discusses other hardware considerations.

13.1 MINIMUM CONNECTIONS

Table 13-1 lists the signals that are required for the device to function and Figure 13-1 shows the connections for a minimum configuration.

 

 

Table 13-1. Minimum Required Signals

Signal

Type

Description

Name

 

 

 

 

 

ANGND

GND

Analog Ground

 

 

ANGND must be connected for A/D converter and port 0 operation (also port 1 on

 

 

the 8XC196MC and MD). ANGND and VSS should be nominally at the same

 

 

potential.

 

 

 

RESET#

I/O

Reset

 

 

A level-sensitive reset input to and open-drain system reset output from the micro-

 

 

controller. Either a falling edge on RESET# or an internal reset turns on a pull-down

 

 

transistor connected to the RESET# pin for 16 state times. In the powerdown and

 

 

idle modes, asserting RESET# causes the chip to reset and return to normal

 

 

operating mode. The 8XC196MH provides the option of preventing an internal reset

 

 

from generating a reset on the external pin (see “Resetting the Device” on page

 

 

13-8). After a device reset, the first instruction fetch is from 2080H.

 

 

 

VCC

PWR

Digital Supply Voltage

 

 

Connect each VCC pin to the digital supply voltage.

 

 

 

VPP

PWR

Programming Voltage

 

 

During programming, the VPP pin is typically at +12.5 V (VPP voltage). Exceeding the

 

 

maximum VPP voltage specification can damage the device.

 

 

VPP also causes the device to exit powerdown mode when it is driven low for at least

 

 

50 ns. Use this method to exit powerdown only when using an external clock source

 

 

because it enables the internal phase clocks, but not the internal oscillator.

 

 

On devices with no internal nonvolatile memory, connect VPP to VCC.

 

 

 

VREF

PWR

Reference Voltage for the A/D Converter

 

 

This pin also supplies operating voltage to both the analog portion of the A/D

 

 

converter and the logic used to read port 0 (also port 1 in the 8XC196MC and

 

 

8XC196MD).

 

 

 

VSS

GND

Digital Circuit Ground

 

 

Connect each VSS pin to ground through the lowest possible impedance path.

 

 

 

13-1

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Intel 8XC196MH, 8XC196MD, 8XC196MC manual Minimum Connections, Minimum Required Signals, Reset#