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diff --git a/docs/ultraplus.html b/docs/ultraplus.html index e5706e6..da109b5 100644 --- a/docs/ultraplus.html +++ b/docs/ultraplus.html @@ -249,4 +249,19 @@ can be used as an open-drain IO using the standard IO cell.</p> <tr><td>CURRENT_MODE</td><td>(0, 28, CBIT_4)</td></tr> </table> + +<h2>IO Changes</h2> +<p>The IO tiles contain a few new bits compared to earlier ice40 devices. + The bits <span style="font-family:monospace">padeb_test_0</span> and + <span style="font-family:monospace">padeb_test_1</span> are set for all pins, + even unused ones, unless set as an output.</p> +<p>There are also some new bits used to control the pullup strength:</p> +<table class="ctab"> +<tr><th>Strength</th><th>Cell 0</th><th>Cell 1</th></tr> +<tr><td>3.3kΩ</td><td>cf_bit_32<br/>B7[10]</td><td>cf_bit_36<br/>B13[10]</td></tr> +<tr><td>6.8kΩ</td><td>cf_bit_33<br/>B6[10]</td><td>cf_bit_37<br/>B12[10]</td></tr> +<tr><td>10kΩ</td><td>cf_bit_34<br/>B7[15]</td><td>cf_bit_38<br/>B13[15]</td></tr> +<tr><td>100kΩ<br/>(default)</td><td>!cf_bit_35<br/>!B6[15]</td><td>!cf_bit_39<br/>!B12[15]</td></tr> + +</table> </body></html> |