From 545fca63356d1966665884d09e818282f18a9ecc Mon Sep 17 00:00:00 2001 From: Terence Boldt Date: Tue, 17 Nov 2020 09:44:56 -0500 Subject: [PATCH] Update README.md --- README.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/README.md b/README.md index ce76392..eb13db4 100644 --- a/README.md +++ b/README.md @@ -4,7 +4,7 @@ Apple II expansion card using a Raspberry Pi for I/O ![Image of Board](/Hardware/Apple2IORPi.jpg) ## Project Status -This is a very early stage project. Currently one partially completed physical prototype exists that sends data unidirectional from the Raspberry Pi Zero W to the Apple II via 8 bit parallel data bus. The schematics are incomplete but now include bidirectional communications. There is no firmware or PCB design yet, nor code for the RPi. +This is a very early stage project. Currently one partially completed physical prototype exists that sends data unidirectional from the Raspberry Pi Zero W to the Apple II via 8 bit parallel data bus. The current design was reviewed and showed that the voltage divider resistors are wired incorrectly and they should be replaced anyway with a 74LVC245 to handle 3.3V and 5V level shifting. The schematics and PCB layout will be changing significantly over the coming weeks. ## Purpose The purpose of this project is to provide I/O for an Apple II series 8 bit computer via a Raspberry Pi Zero W which is powered by the Apple II expansion bus. This could be expanded to use the RPi for more complex processing as per request from the Apple II. For example, the Apple II could request a web page or application and the RPi could calculate this in Apple II hi-res graphics mode and send the image data back to the II for display purposes.