Editing Acorn R140 (section)

=== Backup batteries ===

Two AA (LR6) alkaline cells in a battery nest power the clock and the configuration memory. Acorn's guide says to change them once a year.<ref name="ops" /> Old cells leak and corrode the holder and board; see [[Battery Explosion, Capacitor or Corrosion Damage]] and the battery section of the [[Acorn Archimedes 400/1 Series Maintenance Guide|400/1 maintenance guide]].

# Log in as root, close RISC iX down with <code>halt -RISCOS</code>, type <code>*STATUS</code> and write down the configuration, which will be lost.
# Type <code>*Shutdown</code> to park the hard disc, then switch off and unplug.
# Remove the three screws at the top of the back panel and the screws on each side, then slide the top cover back far enough to expose the front half of the machine.
# The battery nest is at the front right-hand corner as seen from the back. Leave its flying lead to the main board connected. Fit the new cells the right way round; the nest will accept them reversed.
# Refit the cover, hold down R while switching on to reset the configuration to factory settings, then use <code>*STATUS</code> and <code>*CONFIGURE</code> to restore the settings you noted. Reset the date and time.<ref name="ops" />