Atari Portfolio Technical Reference Guide

Atari's developer-facing hardware and software reference for the Atari Portfolio, 1989. The hardware sections cover the 80C88 and the custom ASIC, the memory map, the 240 × 64 super-twist LCD subsystem, the credit-card memory cards and the lithium back-up cell each card contains, the 60-pin expansion connector and the RS-232 interface. Section 2.5 is the power supply: the three AA cells and the step-up switching regulator, the four power modes, and the VCC, 5VS, VRAM, VEXT and BATD lines with their voltages and current limits — including the internal capacitor that backs up system RAM during a battery change.

Download the Atari Portfolio Technical Reference Guide here: File:Atari Portfolio Technical Reference Guide.pdf