Garmin Base Time

A minimalist, elegant, nerdy, typography-focused Garmin Connect IQ watch face that displays the current time using base $n$ ($n = 2..16$) numerals.

Available from Garmin Connect IQ Developer portal or through the Connect IQ mobile app.

Note
Base Time is part of a collection of unconventional Garmin watch faces. It has been developed for fun, as a proof of concept, and as a learning experience. It is shared as is as an open source project, with no commitment to long term maintenance and further feature development.

Please use issues to provide bug reports or feature requests.
Please use discussions for any other comments.

All feedback is wholeheartedly welcome.

Contents

• Base n time
• Features
• Fonts
• Build, test, deploy

Base n time

A positional system is a numeral system in which the contribution of a digit to the value of a number is the value of the digit multiplied by a factor determined by the position of the digit. In the commonly used decimal positional number system, the total value of a numeral is calculated by multiplying each digit by the respective power of 10, and summing those up.

For example, the value of $123_{10}$ (123 in base 10, or decimal) is calculated as follows: $3 \times 10^0 + 2 \times 10^1 + 1 \times 10^2 = 3 + 20 + 100 = 100$. (Note that the calculation is show in the decimal system.)

Besides decimal, positional systems with other bases are in use. In computing, it is common to represent numbers in octal (base 8) and hexadecimal (base 16) systems.

For example, the value of $123_{16}$ (123 in base 16, or hexadecimal) is calculated as follows: $3 \times 16^0 + 2 \times 16^1 + 1 \times 16^2 = 3 + 32 + 256 = 291$. (Note that the calculation is show in the decimal system.)

The Garmin Base Time watch face displays time as hours and minutes in a base-$n$ number system, with the base $n$ set to an integer between 2 and 16. The following table names the available number systems:

System	Base (decimal)	Base (n+1)
Binary	2	2
Ternary	3	3
Quaternary	4	4
Quinary	5	5
Senary	6	6
Septenary	7	7
Octal	8	8
Nonary	9	9
Decimal	10	A
Undecimal	11	B
Duodecimal	12	C
Tridecimal	13	D
Tetradecimal	14	E
Pentadecimal	15	F
Hexadecimal	16	G

Note
The base of the currently used number system is displayed as a subscript, using a smaller, colored font. The convention is to use the corresponding numeral in the next higher ($n+1$) number system. For example:

• The octal (base 8) system is indicated with the digit 8 from the nonal (base 9) system; note that there is no digit 8 in the octal system. (Conveniently, 8 is also a digit in the decimal system, with the same value as 8 in the nonal system.)
• The hexadecimal (base 16) system is indicated with the digit G from the heptadecimal (base 17) system; note that there is no digit G in the hexadecimal system. (There also is no digit G in the decimal system.)

This convention has been chosen to consistently display all system base indicators with one digit. The alternatve of using the decimal system would lead to double-digit indicators for the decimal system and above. (Using a base-$n$ numeral to indicate base $n$ was not an option, as in any number system that numeral would be... 10.)

The base can be selected in the user settings menu in the device. Optionally, the user may turn on standard time, displayed in smaller font below the decimal time, using on-watch customization settings.

Features

The Base Time watch face supports the following features:

Screenshot	Description
	Decimal time The current time as decimal numerals, with the suffix A (unidecimal for 'ten') indicating the base-10 (decimal) number system. The time is displayed in a single line, with hour digits in white bold font, and minutes digits in light gray regular font.
	Binary time Time in base-n with n = 2, 3. The time is displayed as hour digits in white bold font in one line, and minutes digits in light gray regular font in the next line. The base can be changed by the user with a setting in the Customize menu on the device.
	Standard time The standard time is optionally displayed in smaller light gray font beneath the base-n time; here, hexadecimal, with G being sixteen in the heptadecimal (base 17) number system. The standard time can be toggled on and of by the user with a setting in the Cutomize menu on the device. Time in base-n with n = 4..16 is displayed in a single line, as in Decimal time above.

Fonts

The Base Time watch face uses custom fonts:

• SUSEMono for the Base-n time (hours and base indicators in SUSEMono-Bold, minutes in SUSEMono-Regular).
• Ubuntu for standard time (Ubuntu-Regular).

The development of Garmin watch faces motivated the implementation of two useful tools:

• A TTF to FNT+PNG converter (ttf2bmp).
  Garmin watches use non-scalable fixed-size bitmap fonts, and cannot handle variable size True Type fonts directly.
• An font scaler automation tool (garmin-font-scaler).
  Garmin watches come in a variety of shapes and resolutions, and bitmap fonts need to be scaled for each device proportionally to its resolution.

The font development proceeded as follows:

• The fonts were downloaded from Google Fonts as True Type (.ttf) fonts.
• The fonts were converted to bitmaps as .fnt and .png pairs using the open source command-line ttf2bmp converter.
• The font sizes were established to match the Garmin Fenix 7X Solar watch 280x280 pixel screen resolution.
• The fonts were then scaled proportionally to match other screen sizes available on Garmin watches using the garmin-font-scaler tool.

The table below lists all font sizes provided for the supported screen resolutions.

Resolution	Shape	Element	Font	Size
148 x 205	rectangle	Double line hour	SUSEMono bold	26
148 x 205	rectangle	Double line minutes	SUSEMono regular	26
148 x 205	rectangle	Double line system base	SUSEMono bold	13
148 x 205	rectangle	Single line hour	SUSEMono bold	32
148 x 205	rectangle	Single line minutes	SUSEMono regular	32
148 x 205	rectangle	Single line system base	SUSEMono bold	16
148 x 205	rectangle	Standard time	Ubuntu regular	16
176 x 176	semi-octagon	Double line hour	SUSEMono bold	31
176 x 176	semi-octagon	Double line minutes	SUSEMono regular	31
176 x 176	semi-octagon	Double line system base	SUSEMono bold	16
176 x 176	semi-octagon	Single line hour	SUSEMono bold	38
176 x 176	semi-octagon	Single line minutes	SUSEMono regular	38
176 x 176	semi-octagon	Single line system base	SUSEMono bold	19
176 x 176	semi-octagon	Standard time	Ubuntu regular	19
215 x 180	semi-round	Double line hour	SUSEMono bold	32
215 x 180	semi-round	Double line minutes	SUSEMono regular	32
215 x 180	semi-round	Double line system base	SUSEMono bold	16
215 x 180	semi-round	Single line hour	SUSEMono bold	39
215 x 180	semi-round	Single line minutes	SUSEMono regular	39
215 x 180	semi-round	Single line system base	SUSEMono bold	19
215 x 180	semi-round	Standard time	Ubuntu regular	19
218 x 218	round	Double line hour	SUSEMono bold	39
218 x 218	round	Double line minutes	SUSEMono regular	39
218 x 218	round	Double line system base	SUSEMono bold	19
218 x 218	round	Single line hour	SUSEMono bold	47
218 x 218	round	Single line minutes	SUSEMono regular	47
218 x 218	round	Single line system base	SUSEMono bold	23
218 x 218	round	Standard time	Ubuntu regular	23
240 x 240	round	Double line hour	SUSEMono bold	43
240 x 240	rectangle	Double line hour	SUSEMono bold	43
240 x 240	round	Double line minutes	SUSEMono regular	43
240 x 240	rectangle	Double line minutes	SUSEMono regular	43
240 x 240	round	Double line system base	SUSEMono bold	21
240 x 240	rectangle	Double line system base	SUSEMono bold	21
240 x 240	round	Single line hour	SUSEMono bold	51
240 x 240	rectangle	Single line hour	SUSEMono bold	51
240 x 240	round	Single line minutes	SUSEMono regular	51
240 x 240	rectangle	Single line minutes	SUSEMono regular	51
240 x 240	round	Single line system base	SUSEMono bold	26
240 x 240	rectangle	Single line system base	SUSEMono bold	26
240 x 240	round	Standard time	Ubuntu regular	26
240 x 240	rectangle	Standard time	Ubuntu regular	26
260 x 260	round	Double line hour	SUSEMono bold	46
260 x 260	round	Double line minutes	SUSEMono regular	46
260 x 260	round	Double line system base	SUSEMono bold	23
260 x 260	round	Single line hour	SUSEMono bold	56
260 x 260	round	Single line minutes	SUSEMono regular	56
260 x 260	round	Single line system base	SUSEMono bold	28
260 x 260	round	Standard time	Ubuntu regular	28
280 x 280	round	Double line hour	SUSEMono bold	50
280 x 280	round	Double line hour	SUSEMono bold	50
280 x 280	round	Double line minutes	SUSEMono regular	50
280 x 280	round	Double line minutes	SUSEMono regular	50
280 x 280	round	Double line system base	SUSEMono bold	25
280 x 280	round	Double line system base	SUSEMono bold	25
280 x 280	round	Single line hour	SUSEMono bold	60
280 x 280	round	Single line hour	SUSEMono bold	60
280 x 280	round	Single line minutes	SUSEMono regular	60
280 x 280	round	Single line minutes	SUSEMono regular	60
280 x 280	round	Single line system base	SUSEMono bold	30
280 x 280	round	Single line system base	SUSEMono bold	30
280 x 280	round	Standard time	Ubuntu regular	30
280 x 280	round	Standard time	Ubuntu regular	30
320 x 360	rectangle	Double line hour	SUSEMono bold	57
320 x 360	rectangle	Double line minutes	SUSEMono regular	57
320 x 360	rectangle	Double line system base	SUSEMono bold	29
320 x 360	rectangle	Single line hour	SUSEMono bold	69
320 x 360	rectangle	Single line minutes	SUSEMono regular	69
320 x 360	rectangle	Single line system base	SUSEMono bold	34
320 x 360	rectangle	Standard time	Ubuntu regular	34
360 x 360	round	Double line hour	SUSEMono bold	64
360 x 360	round	Double line minutes	SUSEMono regular	64
360 x 360	round	Double line system base	SUSEMono bold	32
360 x 360	round	Single line hour	SUSEMono bold	77
360 x 360	round	Single line minutes	SUSEMono regular	77
360 x 360	round	Single line system base	SUSEMono bold	39
360 x 360	round	Standard time	Ubuntu regular	39
390 x 390	round	Double line hour	SUSEMono bold	70
390 x 390	round	Double line minutes	SUSEMono regular	70
390 x 390	round	Double line system base	SUSEMono bold	35
390 x 390	round	Single line hour	SUSEMono bold	84
390 x 390	round	Single line minutes	SUSEMono regular	84
390 x 390	round	Single line system base	SUSEMono bold	42
390 x 390	round	Standard time	Ubuntu regular	42
416 x 416	round	Double line hour	SUSEMono bold	74
416 x 416	round	Double line minutes	SUSEMono regular	74
416 x 416	round	Double line system base	SUSEMono bold	37
416 x 416	round	Single line hour	SUSEMono bold	89
416 x 416	round	Single line minutes	SUSEMono regular	89
416 x 416	round	Single line system base	SUSEMono bold	45
416 x 416	round	Standard time	Ubuntu regular	45
454 x 454	round	Double line hour	SUSEMono bold	81
454 x 454	round	Double line minutes	SUSEMono regular	81
454 x 454	round	Double line system base	SUSEMono bold	41
454 x 454	round	Single line hour	SUSEMono bold	97
454 x 454	round	Single line minutes	SUSEMono regular	97
454 x 454	round	Single line system base	SUSEMono bold	49
454 x 454	round	Standard time	Ubuntu regular	49

Build, test, deploy

To modify and build the sources, you need to have installed:

• Visual Studio Code with Monkey C extension.
• Garmin Connect IQ SDK.

Consult Monkey C Visual Studio Code Extension for how to execute commands such as build and test to the Monkey C runtime.

You can use the included Makefile to conveniently trigger some of the actions from the command line.

# build binaries from sources
make build

# run unit tests -- note: requires the simulator to be running
make test

# run the simulation
make run

# clean up the project directory
make clean

To sideload your application to your Garmin watch, see developer.garmin.com/connect-iq/connect-iq-basics/your-first-app.