From bfeba8c6497e928cbc4da85a467740959d6cd133 Mon Sep 17 00:00:00 2001 From: techav <76832805+techav-homebrew@users.noreply.github.com> Date: Thu, 20 May 2021 00:10:00 -0500 Subject: [PATCH] Update README.md --- README.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/README.md b/README.md index 0c5d73f..df34374 100644 --- a/README.md +++ b/README.md @@ -1,7 +1,7 @@ # SE-VGA Simple CPLD project to mirror the Mac SE video over VGA. No scaling is performed -- the Mac 512x342 video is displayed letterboxed (black borders) in a 640x480 frame. -Circuit uses a single AFT1508AS-100AU CPLD, 32kx8 15ns SRAM, and a 25.175MHz can oscillator, along with some passives. +Circuit uses a single AFT1508AS-100AU CPLD, a pair of 256kbit (32kx8) 15ns SRAM, and a 25.175MHz can oscillator, along with some passives. Plugs into SE PDS slot and snoops writes to the frame buffer memory locations. Writes are cached and copied to VRAM. @@ -19,7 +19,7 @@ The Mac SE primary framebuffer starts at 0x5900 below the top of RAM. Since it's | 000 | 0x07a700 | 0x072700 | 0x080000 | 0.5MB | `[256kB 256kB][ --- --- ]` | ## CPLD Pin Assignments -Logic uses nearly all available resources in the 128-macrocell CPLD. Attempting to order the I/O pins in a manner more favorable for board layout would just waste precious few remaining resources. Fitter pinout stands. +Logic uses nearly all available resources in the 128-macrocell CPLD. |signal|Direction|Pin| |---|---|---|