From 690922dd2f5025c51716e9e4145434662f08fc14 Mon Sep 17 00:00:00 2001 From: Luke Kenneth Casson Leighton Date: Fri, 24 May 2019 18:17:43 +0100 Subject: [PATCH] add shadowing description --- 3d_gpu/6600scoreboard.mdwn | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/3d_gpu/6600scoreboard.mdwn b/3d_gpu/6600scoreboard.mdwn index a65c8198b..f223cdf49 100644 --- a/3d_gpu/6600scoreboard.mdwn +++ b/3d_gpu/6600scoreboard.mdwn @@ -95,6 +95,10 @@ Shadowing is important as it is the fundamental basis of: Modifications to the shadow circuit below allow the shadow flip-flops to be automatically reset after a Function Unit "dies". Without these modifications, the shadow unit may spuriously fire on subsequent re-use -due to some of the latches being left in the previous state. +due to some of the latches being left in a previous state. + +Note that only "success" will cause the latch to reset. Note also +that the introduction of the NOT gate causes the latch to be more like +a DFF (register). [[!img shadow.jpg]] -- 2.30.2