77 on an abacus

This soroban layout for 77 can be understood rod by rod: the millions column remains empty on this column; the hundred-thousands column is clear with no active beads; the ten-thousands column is set to zero; the thousands column has no beads moved to the beam; the hundreds column remains empty on this column; the tens column marks 7 with the top bead touching the beam and 2 lower beads raised; the ones column reads 7 because the upper bead is engaged and 2 lower beads are slid up.

1. Step 1. Begin with a reset soroban: upper beads released and all lower beads resting below the beam.
2. Step 2. Set the millions column for 0. Here, the millions column remains empty on this column.
3. Step 3. Adjust the hundred-thousands column to 0. the hundred-thousands column is clear with no active beads.
4. Step 4. Configure the ten-thousands rod for 0. That means the ten-thousands column is set to zero.
5. Step 5. On the thousands column, show 0. In practice, the thousands column has no beads moved to the beam.
6. Step 6. Set the hundreds column for 0. Here, the hundreds column remains empty on this column.
7. Step 7. Configure the tens rod for 7. That means the tens column marks 7 with the top bead touching the beam and 2 lower beads raised.
8. Step 8. On the ones column, show 7. In practice, the ones column reads 7 because the upper bead is engaged and 2 lower beads are slid up.
9. Step 9. Read the rods from left to right to confirm that the soroban now represents 77.