diff --git a/src/libvterm/t/run-test.pl b/src/libvterm/t/run-test.pl
index 2e359cc..7d5cc7b 100644
--- a/src/libvterm/t/run-test.pl
+++ b/src/libvterm/t/run-test.pl
@@ -139,17 +139,23 @@
    # ?screen_row assertion is emulated here
    elsif( $line =~ s/^\?screen_row\s+(\d+)\s*=\s*// ) {
       my $row = $1;
-      my $row1 = $row + 1;
-      my $want = eval($line);
+      my $want;
+
+      if( $line =~ m/^"/ ) {
+         $want = eval($line);
+      }
+      else {
+         # Turn 0xDD,0xDD,... directly into bytes
+         $want = pack "C*", map { hex } split m/,/, $line;
+      }
 
       do_onetest if defined $command;
 
-      # TODO: may not be 80
-      $hin->print( "\?screen_chars $row,0,$row1,80\n" );
+      $hin->print( "\?screen_chars $row\n" );
       my $response = <$hout>;
       chomp $response;
 
-      $response = pack "C*", map hex, split m/,/, $response;
+      $response = pack "C*", map { hex } split m/,/, $response;
       if( $response ne $want ) {
          print "# line $linenum: Assert ?screen_row $row failed:\n" .
                "# Expected: $want\n" .