G8PPBase + 8085

Introduction

This is a two-board configuration consists of a G8PP in baseline configuration and a simple 8085 CPU board on RC2014 backplane.

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8085 CPU Card

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Schematic of PCB 8085 CPU card

Gerber photoplots of 8085 CPU card

Engineering change of PCB 8085 CPU card

  1. A 1K pull-up resistor is required between X1 input and VCC so clock input swings from 0.8V (low) to 4.0V (high). At the solder side of PCB, install a 1/8 1K resistor between pin 1 (X1) and pin 40 (VCC) of 8085

Prototype 8085 CPU Card

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This is a prototype of the 8085 CPU card. It is superseded by the PC board version.

Schematic of prototype 8085 CPU card

RC2014 Signal Definition

The following RC2014 signals are redefined for G8PPBase+8085

  • RC2014 Pin 19 (nM1) — ALE (8085 pin 30)
  • RC2014 Pin 23 (nMREQ) — IOnM (8085 pin 34)
  • RC2014 Pin 24 (nWR) — nWR (8085 pin 31)
  • RC2014 Pin 25 (nRD) — nRD (8085 pin 32)
  • RC2014 Pin 26 (nIORQ) — INTA (8085 pin 11)
  • RC2014 Pin 37 (Spare 1) — HLD (8085 pin 39)
  • RC2014 Pin 38 (Spare 2) — RDY (8085 pin 35)
  • RC2014 Pin 39 (Spare 3) — TRAP (8085 pin 6)

G8PP Baseline Configuration

G8PPBase+8085

Serial Bootstrap

8085 Monitor

CP/M-2.2 BIOS/CCP/BDOS

CP/M 2.2 distribution files

Manuals and Instructions

Getting started with G8PPBase+8085 ←configure altera epm7128, load bootstrap, load 8085 monitor, load cp/m

8085 Monitor manual

builderpages/plasmo/g8pp/g8ppbase8085.txt · Last modified: 2020/05/09 22:30 by plasmo
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