According to the errata and the updated spec:

US-ASCII-7bit-packed, the alignment is 1-bit (textual data in this encoding may
appear on any bit boundary, i.e., no byte alignment is required).

However, when I set this up I get the same error I get for other encodings:

[error] Test edu.illinois.ncsa.daffodil.section11.content_framing_properties.TestContentFramingProperties.test_alignmentPacked7BitASCII failed: java.lang.Exception: Schema Definition Error: The given alignment (4 bits) must be a multiple of the encoding specified alignment (8 bits) for (String) when representation='text'. Encoding: US-ASCII-7-BIT-PACKED Schema context: element.e6. Location line 208 column 101 in file:/home/jchab/NGF/dfdl/daffodil-test/target/scala-2.9.2/test-classes/edu/illinois/ncsa/daffodil/section11/content_framing_properties/ContentFramingProps.tdml.

The test is alignmentPacked7BitASCII in the following files:

daffodil-test/src/test/resources/edu/illinois/ncsa/daffodil/section11/content_framing_properties/ContentFramingProps.tdml
daffodil-test/src/test/scala-debug/edu/illinois/ncsa/daffodil/section11/content_framing_properties/TestContentFramingPropertiesDebug.scala
daffodil-test/src/test/scala/edu/illinois/ncsa/daffodil/section11/content_framing_properties/TestContentFramingProperties.scala