Mares Smart setup guide

Two-button watch-style dive computer (Mares RGBM). Air, Nitrox (up to 3 gases), bottom timer and apnea modes; manual altitude setting; user-replaceable CR2430 battery. This guide covers units with serial number above 52061.

Buttons

Button	Where	What it does
`UP/ENTER`	side button labelled UP/ENTER	Press: next item / increase / change top row in a dive. Press and hold (1 s): enter or confirm.
`DOWN/ESC`	side button labelled DOWN/ESC	Press: previous item / decrease / change bottom row in a dive. Press and hold (1 s): go back; backlight from the time-of-day screen and in a dive.

Turn on / wake

Short press of a button = scroll/change; press and hold for 1 second = UP: enter/confirm, DOWN: back (or backlight from the time-of-day screen).

The Smart is also a watch: its normal home screen is the time of day.
Manual p. 6
If the screen is blank (sleep mode), press either button to wake it up.
PressUP/ENTER
Manual p. 9
Before the dive, press UP until PrE dIVE appears, then press and hold UP. This is the ready-to-dive mode.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
Without pre-dive, the dive still starts, but up to 20 seconds late. After 3 minutes in pre-dive with no button press it goes back to the watch screen.
Manual p. 6
Press and hold DOWN to leave a menu and go back one level.
HoldDOWN/ESC
Manual p. 4

Date and time

From the time-of-day screen, press UP until SEt appears, then press and hold UP to open it.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
Press UP or DOWN to reach SEt tIME, then press and hold UP.
PressUP/ENTERHoldUP/ENTER
Manual p. 7
Press either button to scroll the options: time format, time, date, wake-up alarm and second time.
PressUP/ENTER
Manual p. 9
Press and hold UP to edit an option, press either button to change the blinking value, then press and hold UP to confirm.
HoldUP/ENTERPressUP/ENTERHoldUP/ENTER
Manual p. 9

Units (m/ft, °C/°F)

From the time-of-day screen, press UP until SEt appears, then press and hold UP to open it.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
With SEt dIVE shown, press and hold UP.
HoldUP/ENTER
Manual p. 7
Press UP or DOWN to reach UNItS, then press and hold UP to edit it.
PressUP/ENTERHoldUP/ENTER
Manual p. 7
Choose metric (m, °C) or imperial (ft, °F) with UP/DOWN, then press and hold UP to confirm. Depth and temperature change together.
PressUP/ENTERHoldUP/ENTER
Manual p. 8

Water type (salt/fresh)

From the time-of-day screen, press UP until SEt appears, then press and hold UP to open it.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
With SEt dIVE shown, press and hold UP.
HoldUP/ENTER
Manual p. 7
Press UP or DOWN to reach WAtR, then press and hold UP to edit it.
PressUP/ENTERHoldUP/ENTER
Manual p. 7
Choose SALt, FRESH or EN13319 with UP/DOWN, then press and hold UP to confirm.
PressUP/ENTERHoldUP/ENTER
Manual p. 8
A wrong water type changes the shown depth by 1–3%. The decompression calculation is based on pressure and is not affected.
Manual p. 8

Dive mode (Air / Nitrox / Gauge)

From the time-of-day screen, press UP until MOdE appears, then press and hold UP to open it.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
Press UP or DOWN to choose AIR, EAN (nitrox), BT (bottom timer) or APNEA, then press and hold UP. AIR is the same as 21% with a 1.4 bar limit.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
BT shows only depth, time and temperature. There is no decompression calculation and only the low-battery alarm.
Manual p. 14
You can only choose BT when the computer is fully desaturated (no nitrogen left from earlier dives).
Manual p. 14
After a dive in BT, wait at least 24 hours before diving with a decompression computer.
Manual p. 14
After an uncontrolled ascent or a missed deco stop, Air and Nitrox are blocked for 24 hours; only BT works.
Manual p. 14
APNEA is for breath-hold diving only. Do not use it within 24 hours of a scuba dive.
Manual p. 14

Nitrox O₂% and ppO₂ limit

The manual does not describe any automatic reset of O2% to 21%: the setting stays until you change it.

Open MOdE, choose EAN with UP/DOWN, then press and hold UP.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
Press UP or DOWN to set the oxygen % (O2%). Watch the maximum operating depth (MOD) change.
PressUP/ENTERPressDOWN/ESC
Manual p. 7
Press and hold UP to move to ppO2max, then use UP or DOWN to set it (1.2–1.6 bar; factory setting 1.4 bar).
HoldUP/ENTERPressUP/ENTERPressDOWN/ESC
Manual p. 10
Press and hold UP to save. The G2 OFF screen appears (second gas); press and hold DOWN to leave.
HoldUP/ENTERHoldDOWN/ESC
Manual p. 7
Before every dive and after changing tanks, check that the O2% matches the analysed tank.
Manual p. 7

Conservatism / personal setting

A higher P means a more conservative calculation (more safety margin). The manual suggests it, for example, after a long break or for a hard dive. The dive planner uses the chosen P factor.

From the time-of-day screen, press UP until SEt appears, then press and hold UP to open it.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
With SEt dIVE shown, press and hold UP.
HoldUP/ENTER
Manual p. 7
Press UP or DOWN to reach P FACt, then press and hold UP to edit it.
PressUP/ENTERHoldUP/ENTER
Manual p. 7
Choose P0 (standard), P1 (more conservative) or P2 (most conservative) with UP/DOWN, then press and hold UP to confirm.
PressUP/ENTERHoldUP/ENTER
Manual p. 8
The pre-dive screen shows p+ for P1 and p++ for P2. Nothing is shown for P0.
Manual p. 8

Altitude

Altitude is set by hand. Set it before diving in a mountain lake. Above 3700 m / 12100 ft use bottom timer and altitude tables (p. 8).

From the time-of-day screen, press UP until SEt appears, then press and hold UP to open it.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
With SEt dIVE shown, press and hold UP.
HoldUP/ENTER
Manual p. 7
Press UP or DOWN to reach ALt, then press and hold UP to edit it.
PressUP/ENTERHoldUP/ENTER
Manual p. 7
Choose A0 (sea level to about 700 m / 2300 ft), A1 (to 1500 m / 4900 ft), A2 (to 2400 m / 7900 ft) or A3 (to 3700 m / 12100 ft).
PressUP/ENTER
Manual p. 8
Press and hold UP to confirm. A mountain symbol with 1–3 segments shows A1–A3. No symbol means A0.
HoldUP/ENTER
Manual p. 8

Audible alarms (depth / time)

The manual describes no user-set maximum-depth or dive-time alarm for scuba modes (APNEA mode has its own depth and time alarms, p. 14).

From the time-of-day screen, press UP until SEt appears, then press and hold UP to open it.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
With SEt dIVE shown, press and hold UP.
HoldUP/ENTER
Manual p. 7
Press UP or DOWN to reach ALRM, then press and hold UP to edit it.
PressUP/ENTERHoldUP/ENTER
Manual p. 7
Choose on or off with UP/DOWN, then press and hold UP to confirm. Keep the sound on.
PressUP/ENTERHoldUP/ENTER
Manual p. 8
Built-in alarms (no setup): ascent rate, MOD/ppO2, CNS, missed deco stop and low battery.
Manual p. 10

Reading the log after a dive

From the time-of-day screen, press UP until LOG appears, then press and hold UP to open it.
PressUP/ENTERHoldUP/ENTER
Manual p. 6
The first page sums up all dives: deepest depth, number of dives, hours underwater and coldest water.
Manual p. 9
Press UP or DOWN to scroll through the dives (1 = most recent).
PressUP/ENTERPressDOWN/ESC
Manual p. 9
Page 1 of a dive: max depth, lowest temperature and average depth, time in and out, date and O2%.
Manual p. 9
Press and hold UP for the next page: surface interval, dive time and CNS.
HoldUP/ENTER
Manual p. 9
Press and hold DOWN to go back to the logbook list.
HoldDOWN/ESC
Manual p. 9

Battery

No battery symbol means there is enough charge to dive.
Manual p. 4
A steady battery symbol means a few dives are left. Replace the battery soon.
Manual p. 4
A blinking battery symbol (on the surface) means the battery is too weak. Do not dive: the Smart will not work as a dive computer.
Manual p. 4
INFO shows the battery as OK (good), LO (a few dives left) or KO (too low to dive).
PressUP/ENTERHoldUP/ENTER
Manual p. 10
It uses a user-replaceable CR2430 battery; Mares suggests having it changed at an authorised Mares centre.
Manual p. 16

What the main screen shows

Pre-dive screen: P factor, altitude, time of day and surface interval; with nitrox also O2% and MOD.
Manual p. 6
During the dive: depth, max depth, NO DECO time, dive time, temperature and a nitrogen bar graph.
Manual p. 11
In a deco dive, the NO DECO time is replaced by the deepest stop depth and time and the total ascent time.
Manual p. 12
Nitrogen bar graph: the more black segments, the closer you are to the no-deco limit.
Manual p. 12
Press UP to change the top row: max depth, average depth, MOD (nitrox), deep stop.
PressUP/ENTER
Manual p. 11
Press DOWN to change the bottom row: temperature, O2%, CNS, ppO2, time of day (for 4 seconds).
PressDOWN/ESC
Manual p. 11
Ascent speed replaces the dive time while you go up. At 10 m/min / 30 ft/min or faster it beeps and shows SLOW.
Manual p. 10
Press and hold DOWN for the backlight.
HoldDOWN/ESC
Manual p. 4

Pre-dive check

Tick each item before you get in the water.

No blinking battery symbol; INFO shows OK.
Mode is AIR or EAN as planned, not BT or APNEA.
If EAN: O2% matches the analysed tank and ppO2max is 1.4 bar (or as instructed).
P factor (p+/p++) is as your instructor wants.
Altitude symbol matches the dive site (none = A0 sea level).
Water type (SALt/FRESH/EN13319) matches the dive site.
Audible alarms (ALRM) are on.
PrE dIVE is active before you get in the water.