https://community.nxp.com/t5/Digital-Signal-Controllers/A-single-Data-Byte-0x00-is-transmitted-by-Serial-TX-on-every/m-p/1440371#M2491 <P>Hello <a href="https://community.nxp.com/t5/user/viewprofilepage/user-id/195624">@malikos</a>,</P> <P>What do you mean by startup?</P> <P>When the transmitter gets enabled a preamble of all 1s is loaded into the shift register.</P> <P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="danielmartynek_0-1649319564883.png" style="width: 877px;"><img src="https://community.nxp.com/t5/image/serverpage/image-id/176188iF72559D8F9124C88/image-dimensions/877x130?v=v2" width="877" height="130" role="button" title="danielmartynek_0-1649319564883.png" alt="danielmartynek_0-1649319564883.png" /></span></P> <P>Before that, the port is not controlled by the SCI module.</P> <P>Which pins do you use for the SCI?</P> <P>Can you share the project so that I can test it on my side?</P> <P>&nbsp;</P> <P>Thank you,</P> <P>BR, Daniel</P> <P>&nbsp;</P> <P>&nbsp;</P> Thu, 07 Apr 2022 08:22:57 GMT danielmartynek 2022-04-07T08:22:57Z https://community.nxp.com/t5/Digital-Signal-Controllers/A-single-Data-Byte-0x00-is-transmitted-by-Serial-TX-on-every/m-p/1438741#M2488 <P><SPAN>I am currently using a MC9S12ZVM Family. I am transmitting some data over the serial communication interface. However on every start up A single Data Byte 0x00 is transmitted. Is there any configuration in processor expert which can stop this.</SPAN></P> Tue, 05 Apr 2022 08:29:07 GMT https://community.nxp.com/t5/Digital-Signal-Controllers/A-single-Data-Byte-0x00-is-transmitted-by-Serial-TX-on-every/m-p/1438741#M2488 malikos 2022-04-05T08:29:07Z https://community.nxp.com/t5/Digital-Signal-Controllers/A-single-Data-Byte-0x00-is-transmitted-by-Serial-TX-on-every/m-p/1440371#M2491 <P>Hello <a href="https://community.nxp.com/t5/user/viewprofilepage/user-id/195624">@malikos</a>,</P> <P>What do you mean by startup?</P> <P>When the transmitter gets enabled a preamble of all 1s is loaded into the shift register.</P> <P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="danielmartynek_0-1649319564883.png" style="width: 877px;"><img src="https://community.nxp.com/t5/image/serverpage/image-id/176188iF72559D8F9124C88/image-dimensions/877x130?v=v2" width="877" height="130" role="button" title="danielmartynek_0-1649319564883.png" alt="danielmartynek_0-1649319564883.png" /></span></P> <P>Before that, the port is not controlled by the SCI module.</P> <P>Which pins do you use for the SCI?</P> <P>Can you share the project so that I can test it on my side?</P> <P>&nbsp;</P> <P>Thank you,</P> <P>BR, Daniel</P> <P>&nbsp;</P> <P>&nbsp;</P> Thu, 07 Apr 2022 08:22:57 GMT https://community.nxp.com/t5/Digital-Signal-Controllers/A-single-Data-Byte-0x00-is-transmitted-by-Serial-TX-on-every/m-p/1440371#M2491 danielmartynek 2022-04-07T08:22:57Z