RetroBBS - comp.sys.apple2.programmer - QDStartup masterSCB bits meaning

QDStartup masterSCB bits meaning

<d0817d94-a234-4b72-8020-7baa89e4016fn@googlegroups.com>

https://www.rocksolidbbs.com/devel/article-flat.php?id=234&group=comp.sys.apple2.programmer#234

copy link Newsgroups: comp.sys.apple2.programmer

X-Received: by 2002:a05:622a:10d:b0:2e1:db41:66d with SMTP id u13-20020a05622a010d00b002e1db41066dmr32647474qtw.670.1648643867693;
Wed, 30 Mar 2022 05:37:47 -0700 (PDT)
X-Received: by 2002:a05:6870:8a2b:b0:dd:cfdd:30e1 with SMTP id
p43-20020a0568708a2b00b000ddcfdd30e1mr1990131oaq.16.1648643867268; Wed, 30
Mar 2022 05:37:47 -0700 (PDT)
Path: i2pn2.org!i2pn.org!weretis.net!feeder8.news.weretis.net!proxad.net!feeder1-2.proxad.net!209.85.160.216.MISMATCH!news-out.google.com!nntp.google.com!postnews.google.com!google-groups.googlegroups.com!not-for-mail
Newsgroups: comp.sys.apple2.programmer
Date: Wed, 30 Mar 2022 05:37:47 -0700 (PDT)
Injection-Info: google-groups.googlegroups.com; posting-host=151.47.186.184; posting-account=QzAJCwoAAAC6OlGOAR7kcjrdGEj9YpS-
NNTP-Posting-Host: 151.47.186.184
User-Agent: G2/1.0
MIME-Version: 1.0
Message-ID: <d0817d94-a234-4b72-8020-7baa89e4016fn@googlegroups.com>
Subject: QDStartup masterSCB bits meaning
From: erolfi@gmail.com (Enrico)
Injection-Date: Wed, 30 Mar 2022 12:37:47 +0000
Content-Type: text/plain; charset="UTF-8"

by: Enrico - Wed, 30 Mar 2022 12:37 UTC

I'm struggling to find out the meaning of bit 8 of the masterSCB parameter in a QDStartUp Toolbox call.

I see that a lot of GS apps use to set this bit high.

According to the Toolbox documentation volume 3, this bit should be Reserved!?

masterSCB:
bit 15 -> fUseShadowing
bit 14 -> fFastPortAware
bits 8-13 -> Reserved
bits 0-7 -> SCB

Re: QDStartup masterSCB bits meaning

<464ffa0d-aa90-4c63-b5f0-3717ff0b3c42n@googlegroups.com>

copy mid

https://www.rocksolidbbs.com/devel/article-flat.php?id=235&group=comp.sys.apple2.programmer#235

copy link Newsgroups: comp.sys.apple2.programmer

X-Received: by 2002:a05:620a:318c:b0:67e:d346:4ad9 with SMTP id bi12-20020a05620a318c00b0067ed3464ad9mr23996435qkb.493.1648644104388;
Wed, 30 Mar 2022 05:41:44 -0700 (PDT)
X-Received: by 2002:a05:6870:a10e:b0:dd:bc3a:d2c2 with SMTP id
m14-20020a056870a10e00b000ddbc3ad2c2mr2027748oae.123.1648644103922; Wed, 30
Mar 2022 05:41:43 -0700 (PDT)
Path: i2pn2.org!i2pn.org!weretis.net!feeder6.news.weretis.net!1.us.feeder.erje.net!3.us.feeder.erje.net!feeder.erje.net!border1.nntp.dca1.giganews.com!nntp.giganews.com!news-out.google.com!nntp.google.com!postnews.google.com!google-groups.googlegroups.com!not-for-mail
Newsgroups: comp.sys.apple2.programmer
Date: Wed, 30 Mar 2022 05:41:43 -0700 (PDT)
In-Reply-To: <d0817d94-a234-4b72-8020-7baa89e4016fn@googlegroups.com>
Injection-Info: google-groups.googlegroups.com; posting-host=151.47.186.184; posting-account=QzAJCwoAAAC6OlGOAR7kcjrdGEj9YpS-
NNTP-Posting-Host: 151.47.186.184
References: <d0817d94-a234-4b72-8020-7baa89e4016fn@googlegroups.com>
User-Agent: G2/1.0
MIME-Version: 1.0
Message-ID: <464ffa0d-aa90-4c63-b5f0-3717ff0b3c42n@googlegroups.com>
Subject: Re: QDStartup masterSCB bits meaning
From: erolfi@gmail.com (Enrico)
Injection-Date: Wed, 30 Mar 2022 12:41:44 +0000
Content-Type: text/plain; charset="UTF-8"
Lines: 6

by: Enrico - Wed, 30 Mar 2022 12:41 UTC

Ok, it seems stupid to reply to my own question, but I just found the answer to it on "Apple IIGS Toolbox Changes
for System Software 6.0 (ERS version 2.5)" by David A. Lyons (February 26, 1992)

"Added a QDStartUp MasterSCB bit (value $0100, bit 8) that causes the screen not to
be cleared if it is already being displayed. StartUpTools uses this to avoid wiping
the screen first to black and then to the desktop pattern, when the Window Manager is
also being started up."

Computer programmers do it byte by byte.

devel / comp.sys.apple2.programmer / QDStartup masterSCB bits meaning

Subject	Author
QDStartup masterSCB bits meaning	Enrico
Re: QDStartup masterSCB bits meaning	Enrico