{ This procedure is used in monitor to preset a range of REAL MEMORY
{ ADDRESSES to a specified value. WARNING: no checks are made on the
{ validity of the address range except to verify that the SVA
{ exists in the page table with the 'valid' bit clear. The range of words
{ to be preset must not cross a page boundary.
{
{     MMP$PRESET_REAL_MEMORY (SVA, LENGTH, PRESET_VALUE);
{
{   SVA: (input) This parameter specifies the SVA of the memory to be
{        preset. The memory must not cross a page boundary and must
{        start on a word boundary.
{   LENGTH: (input) This parameter specifies the number of words to
{        be preset.
{   PRESET_VALUE: (input) This parameter specifies the bit pattern
{        to be used to do the preset function.
{    NOTES:
{       - routine will halt if SVA is not 0 MOD 8.
{       - routine will halt if SVA is not in the page table with the
{         'valid' bit CLEAR.
{       - length is rounded down to a multiple of eight bytes.
