Re: A89: checksum (for normal files)

To: assembly-89@lists.ticalc.org
Subject: Re: A89: checksum (for normal files)
From: Chris Davis <fuol@webFreaks.net>
Date: Tue, 20 Jun 2000 20:49:35 -0700 (PDT)
In-Reply-To: <000a01bfdadf$973a0f30$0100a8c0@gandalf>
Reply-To: assembly-89@lists.ticalc.org

You have to sum the bytes of the raw ti89 data, then bitwise AND the
checksum by 0xffff (in C: checksum &= 0xffff).  By 'sum' I don't just mean
counting the total number of bytes, I mean adding the ascii values of each
byte to a running total. The checksum, which is a 2-byte word, is written
in little endian (intel) format, just after the data.

On Tue, 20 Jun 2000, Jeremie Knusel wrote:

> 
> hello
> does anyone know how to calculate the checksum for a 89t file? (to make it
> sendable with the ti-graph link program)
> I know there are programs to add it automatically but I look for the method
> to calculate it
> bye
> Jeremie Knusel
> 
>

References:

A89: checksum (for normal files)

From: "Jeremie Knusel" <elendur@freesurf.ch>