A funny protection by RG: Le prisonnier

Subject: A funny protection by RG: Le prisonnier
From: Antoine Vignau <antoine.vignau@laposte.net>
Date: Sun, 26 Aug 2012 03:58:28 -0700 (PDT)
Bytes: 1175
Complaints-to: groups-abuse@google.com
In-reply-to: <975a923d-517d-467e-a0a2-17de308e54f6@googlegroups.com>
Injection-info: glegroupsg2000goo.googlegroups.com; posting-host=88.174.196.55; posting-account=c4quJwoAAABUj_DOmUN3HIuXxN1tF7gT
Newsgroups: comp.sys.apple2
Organization: http://groups.google.com
References: <975a923d-517d-467e-a0a2-17de308e54f6@googlegroups.com>
User-agent: G2/1.0

hum, no track $23 but weird tracks $21 and $22. probably some nibble count or check...
antoine

References:
- A funny protection by RG: Le prisonnier
  - From: Antoine Vignau <antoine.vignau@laposte.net>