Dataman S4 - Manual (Page 7)

DATAMAN S4 MANUAL
Introduction to S4 7
beeping noises. It will switch itself off at the
end of this time. If you press a key during the
beeping, power-down is prevented. No data is
lost by power-down, but you have to switch-off-
and-on-again to get the power back.
If a charger is connected, S4 remains on. If the
battery runs down to the 25% point, it is
automatically recharged.
S4 also powers down when it believes that the
battery is getting too low - less than 8.4 volts.
At this level, data and program can be
preserved, but nothing else works. It warns you
first, both audibly and with a message. If the
voltage goes below 8 volts it turns off
immediately without warning. S4 cannot do
anything useful without power, except preserve
the memory contents.
The only cure is to charge the battery.
Memory Upgrade to 512K
At some point, you may wish to upgrade the
user RAM in your S4 from 1Mbit to the full
4Mbit (512K bytes). All Dataman sales offices
keep a suitable part in stock, or you may wish
to purchase it through a local memory vendor.
The correct part should be a 4Mbit (512K x 8)
low power static RAM in a 32 pin JEDEC DIL
package. We recommend fitting a part with an
access time of 100ns or less.
The upgrade procedure is simple. First switch
off then:
1. Remove the back of the case by
unscrewing the four retaining screws