Subversion Repositories tv80

<?xml version="1.0"?>
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<rfc>
<front>
<title>tv80 Core Documentation</title>
<author initials="G." surname="Hutchison" fullname="Guy Hutchison">
<organization>OpenCores.org</organization>
<email>ghutchis@opencores.org</email>
</author>
<date month="October" year="2004" />
<area>General</area>
<keyword>private</keyword>
<keyword>XML</keyword>
<keyword>Extensible Markup Language</keyword>
<abstract><t>
A synthesizable 8-bit microprocessor which is instruction-set compatable
with the Z80, targetted at embedded and system-on-a-chip designs.
</t></abstract>
</front>
<middle>
<section title="Verification Environment">
 <section title="Memory Map">
<t>
Environment memory space is divided into a 32k ROM region and a 32k RAM
region, as follows:

<figure>
<artwork>
  0000-7FFF:  ROM
  8000-FFFF:  RAM
</artwork>
</figure>

<t>Environment I/O space is allocated as follows:</t>

<figure>
<artwork>
  00-0F:  Unused
  10-1F:  Test devices
  20-7F:  Unused
  80-9F:  Environment control
  A0-FF:  Unused
</artwork></figure>
</t>
 </section>
 <section title="Control Registers">
The tv80 environment is controlled by the program under simulation.  The
program can affect the environment through a set of control registers,
which are mapped into I/O space.

  <section title="Simulation control (0x80)">

<figure>
<artwork>
        Write '01' to end simulation with test passed
        Write '02' to end with test failed
        Write '03' to turn on dumping
        Write '04' to turn off dumping
</artwork>
</figure>
  </section>

  <section title="Message output (0x81)">
<t>
        Write characters to this port one at a time.  When the
        newline ('\n', ASCII 0x0A) character is written, the 
        environment will print out the collected string.
</t>
  </section>
  <section title="Timeout control (0x82)">

<figure>
<artwork>
        Bit[0] enables the timeout counter
        Bit[1] resets the counter to 0
        Timeout counter defaults to enabled at simulation start
</artwork>
</figure>

  </section>
  <section title="Max timeout (0x84, 0x83)">
   <t>
        Holds 16-bit timeout value (amount of time in clocks before
        timeout error occurs).
   </t>
  </section>
  <section title="Interrupt countdown (0x90)">
    <t>
        When set, starts a countdown (in clocks) until assertion of
        the INT_N signal.
   </t>
  </section>

 </section>
</section>
</middle>
<back>
</back>
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