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doc: More steps in the Quickstart Guide.
Signed-off-by: Christophe de Dinechin <christophe@dinechin.org>
This commit is contained in:
Christophe de Dinechin
parent
51e56ad2c7
commit
31e76f6588
3 changed files with 423 additions and 27 deletions
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@ -6,23 +6,155 @@ DB48X, and show you how to use it efficiently.
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[](https://www.youtube.com/watch?v=rVWy4N0lBOI&list=PLz1qkflzABy-Cs1R07zGB8A9K5Yjolmlf)
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## Installation process
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## Arithmetic operations
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**Downloading the software**
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Let's compute the area of a room made of a main section that is 6 meters by 8.3
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meters, with an additional smaller section that is 3.5 meters by 2.8.
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**Connecting the calculator to a computer**
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A first way to do it is to use the reverse polish stack-based approach, by
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typing the following sequence of keys: _6_, _ENTER_, _8_, _._, _3_, _×_, _3_,
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_._, _5_, _ENTER_, _2_, _._, _8_, _×_, _+_. The result, `59.6`, shows on the
|
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stack. Prior to pressing the _+_ key, the intermediate results for the two
|
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multiplications, `49.8` and `9.8`, could be seen on the stack.
|
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|
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**Setup menu system (firmware menus)**
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RPL also supports the standard algebraic notation. Begin the computation with
|
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the _'()_ key. The editor contains quotes, `''` with the cursor between
|
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them. The cursor shows the latter `A`, indicating algebraic entry. Type _6_,
|
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_×_, _8_, _._, _3_, _+_, _3_, _._, _5_, _×_, _2_, _._, _8_. At this point,
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the text editor should show the whole expression, `'6·8.3+3.5·2.8'`
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or `'6×8.3+3.5×2.8'`. Press `ENTER` and the expression shows up on the
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stack. Hitting the _=_ / _EVAL_ / _SPC_ key (located between the _._ and _+_
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keys) evaluates the expression, to get the result `59.6`.
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|
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**Exposing internal storage as a USB disk**
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Algebraic and reverse-polish computations are equivalent, and can be mixed and
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matched during computations. Using one or the other is stricly a matter of
|
||||
preference. Algebraic data entry makes it easier to view the entire
|
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expression. Reverse-polish makes it easier to see intermediate results.
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**Copying DB48X installation files**
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**Copying DM42 installation files**
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## Fractions
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**Installing the DB48X QSPI file**
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Let us now compute how many pies we need to feed 22 kids if we divide each pie
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in 8 slices. Using the RPL approach, we would type _2_, _2_, _ENTER_, _8_,
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_÷_. Using the algebraic notation, we would type _'()_, _2_, _2_, _÷_, _8_,
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_ENTER_ and then use the _=_ to perform the computation.
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With the default settings, you should see a mixed fraction, `2 ³/₄`. Unlike many
|
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calculators, DB48X by default perform exact computations on fractions instead of
|
||||
using approximate decimal numbers.
|
||||
|
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You can convert that fraction to a decimal value and back using the `Cycle`
|
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command, which is bound to the _EEX_ key. A first press will show `2.75`, and a
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second press will show the value again as fraction `2 ³/₄`.
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|
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## Mathematical functions
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DB48X features a number of mathematical functions. Some of the functions are
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directly available on the keyboard.
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|
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We can compute the length of the diagonal of a rectangle with sides 2m and 3m
|
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using the Pythagorean theorem, and display it in millimeters.
|
||||
|
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In RPL, we can type the following sequence: _2_, _x²_ (🟨 _C_), _3_, _x²_,
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_+_, _√x_ (_C_), _1_, _0_, _0_, _0_, _×_. The decimal result,
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`3 605.55127 546`, is shown on the stack. The digits in the whole part of the
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decimal number are grouped 3 by 3, while the digits in the fractional part are
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grouped 5 by 5.
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|
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In algebraic mode, we can type the following sequence:
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_'()_, _1_, _0_, _0_, _0_, _×_, _√x_,
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_2_, _x²_ (🟨 _C_), _+_, _3_, _x²_, _ENTER_. The mathematical
|
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expresssion shows up on the stack graphically. It can then be evaluated using
|
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the _=_ key, and shows the same result as for RPL mode.
|
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|
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|
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## Mixing algebraic and reverse-polish operations
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|
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In the algebraic expression, we have multiplied by 1000 first, whereas in the
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RPL case, we multiplied by 1000 last. We can also multiply by 1000 last in
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algebraic mode. There are at least two ways to do it.
|
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|
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A first method is to use the arrow key to exit the parentheses around the
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argument of the square root function, as follows: _'()_, _√x_,
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_2_, _x²_, _+_, _3_, _x²_, _▶︎_, _×_, _1_, _0_, _0_, _0_,
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_ENTER_. The expression with the multiplication is then shown on the stack, and
|
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can then be evaluated with the _=_ key.
|
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|
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A second method is to mix and match algebraic and RPL, by typing
|
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the following sequence: _'()_, _√x_, _2_, _x²_, _+_,
|
||||
_3_, _x²_, _ENTER_. At this point, the expression without the
|
||||
multiplication is on the stack. We can then multiply it by 1000 by typing
|
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_1_, _0_, _0_, _0_, _×_. The expression with the multiplication is then shown on
|
||||
the stack, and can then be evaluated with the _=_ key.
|
||||
|
||||
|
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## Trigonometric functions
|
||||
|
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Consider that we need to build a plank ramp. We can ask a number of questions,
|
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like:
|
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|
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* If the plank is 5 meters in length, and the slope is 10 degrees, how high
|
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will it reach?
|
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|
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* If we need to reach 60 cm above ground, what is the required slope?
|
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|
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In RPL, can answer the first question by typing _1_, _0_, _SIN_, _5_,
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_×_. The result is shown in scientific format as `8.68240 88833 5×₁₀⁻¹`.
|
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In algebraic mode, we would type _'()_, _5_, _×_, _SIN_, _1_, _0_, _ENTER_
|
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and then evaluating the expression with _=_. This shows the same result.
|
||||
|
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We can answer the second question using RPL by typing _6_, _0_, _ENTER_, _5_,
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_ENTER_, _1_, _0_, _0_, _×_, _÷_, _sin⁻¹_ (🟨 _J_). The result is shown as
|
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`6.89210 25793 5 °`. This is an example of *unit object*: the value is
|
||||
associated with a unit, in that case the `°` symbol indicating that we use
|
||||
degrees. DB48X supports three other angle modes, radians, grads and fractions of
|
||||
pi (piradians).
|
||||
|
||||
Answering the same question using algebraic mode introduces a new little
|
||||
keyboard trick. Type _'()_, _sin⁻¹_, _6_, _0_, _÷_, _'()_,
|
||||
_5_, _×_, _1_, _0_, _0_, _ENTER_, and then evaluating the expression with the
|
||||
_=_ key. Observe how the second use of the _'()_ key, which inserts parentheses
|
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when used inside an expression.
|
||||
|
||||
|
||||
## Selecting display modes
|
||||
|
||||
The scientific notation may not be the most readable in that case. How do we
|
||||
display this result with three digits? We will use a *menu* for that. Menus are
|
||||
an essential component of the DB48X user interface.
|
||||
|
||||
Let us type 🟨 _O_ (_Disp_). This shows the `DisplayModesMenu`. The menu
|
||||
occupies three rows at the bottom of the screen, with six columns. Menus can
|
||||
give a quick access to 18 functions directly, six more with a single shift 🟨,
|
||||
and yet another six with the second shift 🟦. Hitting the shift key 🟨
|
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repeatedly will highlight the different rows of the menu.
|
||||
|
||||
On the lower row of the menu, the second entry from the left is labeled `Fix`.
|
||||
The `Fix` display mode shows a fixed number of digits after the decimal
|
||||
separator. There are other modes, `Sci` to display in scientific notation, `Eng`
|
||||
to display with engineering multiples (the exponent is a multiple of three), and
|
||||
`Sig` to display at most a given number of digits.
|
||||
|
||||
We can type _3_, _F2_, where _F2_ is the second key from the left on the top row
|
||||
of the keyboard. This activates the `Fix 3` mode, which shows three digits after
|
||||
the decimal separator. The display changes to `0.868` for the answer to the
|
||||
first question, and `6.892 °` for the answer to the second question.
|
||||
|
||||
|
||||
## Displaying the on-line help for a function
|
||||
|
||||
Since the number of available commands in DB48X is quite high, it is useful to
|
||||
be able to consult the built-in help. In order to get help on a command, simply
|
||||
hold the corresponding key until the help shows up. For instance, to get
|
||||
[help about the command](#std) under the `Std` label, simply hold the _F1_ key.
|
||||
|
||||
This also works for normal keyboard operations. For instance, if you hold the
|
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_SIN_ key, you will get the [help about the sine command](#sin).
|
||||
|
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|
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## Complex number operations
|
||||
|
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**Installing the DB48X program file**
|
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|
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## Switching between DM42 and DB48X
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|
|
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150
help/db48x.md
150
help/db48x.md
|
|
@ -939,23 +939,155 @@ DB48X, and show you how to use it efficiently.
|
|||
[](https://www.youtube.com/watch?v=rVWy4N0lBOI&list=PLz1qkflzABy-Cs1R07zGB8A9K5Yjolmlf)
|
||||
|
||||
|
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## Installation process
|
||||
## Arithmetic operations
|
||||
|
||||
**Downloading the software**
|
||||
Let's compute the area of a room made of a main section that is 6 meters by 8.3
|
||||
meters, with an additional smaller section that is 3.5 meters by 2.8.
|
||||
|
||||
**Connecting the calculator to a computer**
|
||||
A first way to do it is to use the reverse polish stack-based approach, by
|
||||
typing the following sequence of keys: _6_, _ENTER_, _8_, _._, _3_, _×_, _3_,
|
||||
_._, _5_, _ENTER_, _2_, _._, _8_, _×_, _+_. The result, `59.6`, shows on the
|
||||
stack. Prior to pressing the _+_ key, the intermediate results for the two
|
||||
multiplications, `49.8` and `9.8`, could be seen on the stack.
|
||||
|
||||
**Setup menu system (firmware menus)**
|
||||
RPL also supports the standard algebraic notation. Begin the computation with
|
||||
the _'()_ key. The editor contains quotes, `''` with the cursor between
|
||||
them. The cursor shows the latter `A`, indicating algebraic entry. Type _6_,
|
||||
_×_, _8_, _._, _3_, _+_, _3_, _._, _5_, _×_, _2_, _._, _8_. At this point,
|
||||
the text editor should show the whole expression, `'6·8.3+3.5·2.8'`
|
||||
or `'6×8.3+3.5×2.8'`. Press `ENTER` and the expression shows up on the
|
||||
stack. Hitting the _=_ / _EVAL_ / _SPC_ key (located between the _._ and _+_
|
||||
keys) evaluates the expression, to get the result `59.6`.
|
||||
|
||||
**Exposing internal storage as a USB disk**
|
||||
Algebraic and reverse-polish computations are equivalent, and can be mixed and
|
||||
matched during computations. Using one or the other is stricly a matter of
|
||||
preference. Algebraic data entry makes it easier to view the entire
|
||||
expression. Reverse-polish makes it easier to see intermediate results.
|
||||
|
||||
**Copying DB48X installation files**
|
||||
|
||||
**Copying DM42 installation files**
|
||||
## Fractions
|
||||
|
||||
**Installing the DB48X QSPI file**
|
||||
Let us now compute how many pies we need to feed 22 kids if we divide each pie
|
||||
in 8 slices. Using the RPL approach, we would type _2_, _2_, _ENTER_, _8_,
|
||||
_÷_. Using the algebraic notation, we would type _'()_, _2_, _2_, _÷_, _8_,
|
||||
_ENTER_ and then use the _=_ to perform the computation.
|
||||
|
||||
With the default settings, you should see a mixed fraction, `2 ³/₄`. Unlike many
|
||||
calculators, DB48X by default perform exact computations on fractions instead of
|
||||
using approximate decimal numbers.
|
||||
|
||||
You can convert that fraction to a decimal value and back using the `Cycle`
|
||||
command, which is bound to the _EEX_ key. A first press will show `2.75`, and a
|
||||
second press will show the value again as fraction `2 ³/₄`.
|
||||
|
||||
|
||||
## Mathematical functions
|
||||
|
||||
DB48X features a number of mathematical functions. Some of the functions are
|
||||
directly available on the keyboard.
|
||||
|
||||
We can compute the length of the diagonal of a rectangle with sides 2m and 3m
|
||||
using the Pythagorean theorem, and display it in millimeters.
|
||||
|
||||
In RPL, we can type the following sequence: _2_, _x²_ (🟨 _C_), _3_, _x²_,
|
||||
_+_, _√x_ (_C_), _1_, _0_, _0_, _0_, _×_. The decimal result,
|
||||
`3 605.55127 546`, is shown on the stack. The digits in the whole part of the
|
||||
decimal number are grouped 3 by 3, while the digits in the fractional part are
|
||||
grouped 5 by 5.
|
||||
|
||||
In algebraic mode, we can type the following sequence:
|
||||
_'()_, _1_, _0_, _0_, _0_, _×_, _√x_,
|
||||
_2_, _x²_ (🟨 _C_), _+_, _3_, _x²_, _ENTER_. The mathematical
|
||||
expresssion shows up on the stack graphically. It can then be evaluated using
|
||||
the _=_ key, and shows the same result as for RPL mode.
|
||||
|
||||
|
||||
## Mixing algebraic and reverse-polish operations
|
||||
|
||||
In the algebraic expression, we have multiplied by 1000 first, whereas in the
|
||||
RPL case, we multiplied by 1000 last. We can also multiply by 1000 last in
|
||||
algebraic mode. There are at least two ways to do it.
|
||||
|
||||
A first method is to use the arrow key to exit the parentheses around the
|
||||
argument of the square root function, as follows: _'()_, _√x_,
|
||||
_2_, _x²_, _+_, _3_, _x²_, _▶︎_, _×_, _1_, _0_, _0_, _0_,
|
||||
_ENTER_. The expression with the multiplication is then shown on the stack, and
|
||||
can then be evaluated with the _=_ key.
|
||||
|
||||
A second method is to mix and match algebraic and RPL, by typing
|
||||
the following sequence: _'()_, _√x_, _2_, _x²_, _+_,
|
||||
_3_, _x²_, _ENTER_. At this point, the expression without the
|
||||
multiplication is on the stack. We can then multiply it by 1000 by typing
|
||||
_1_, _0_, _0_, _0_, _×_. The expression with the multiplication is then shown on
|
||||
the stack, and can then be evaluated with the _=_ key.
|
||||
|
||||
|
||||
## Trigonometric functions
|
||||
|
||||
Consider that we need to build a plank ramp. We can ask a number of questions,
|
||||
like:
|
||||
|
||||
* If the plank is 5 meters in length, and the slope is 10 degrees, how high
|
||||
will it reach?
|
||||
|
||||
* If we need to reach 60 cm above ground, what is the required slope?
|
||||
|
||||
In RPL, can answer the first question by typing _1_, _0_, _SIN_, _5_,
|
||||
_×_. The result is shown in scientific format as `8.68240 88833 5×₁₀⁻¹`.
|
||||
In algebraic mode, we would type _'()_, _5_, _×_, _SIN_, _1_, _0_, _ENTER_
|
||||
and then evaluating the expression with _=_. This shows the same result.
|
||||
|
||||
We can answer the second question using RPL by typing _6_, _0_, _ENTER_, _5_,
|
||||
_ENTER_, _1_, _0_, _0_, _×_, _÷_, _sin⁻¹_ (🟨 _J_). The result is shown as
|
||||
`6.89210 25793 5 °`. This is an example of *unit object*: the value is
|
||||
associated with a unit, in that case the `°` symbol indicating that we use
|
||||
degrees. DB48X supports three other angle modes, radians, grads and fractions of
|
||||
pi (piradians).
|
||||
|
||||
Answering the same question using algebraic mode introduces a new little
|
||||
keyboard trick. Type _'()_, _sin⁻¹_, _6_, _0_, _÷_, _'()_,
|
||||
_5_, _×_, _1_, _0_, _0_, _ENTER_, and then evaluating the expression with the
|
||||
_=_ key. Observe how the second use of the _'()_ key, which inserts parentheses
|
||||
when used inside an expression.
|
||||
|
||||
|
||||
## Selecting display modes
|
||||
|
||||
The scientific notation may not be the most readable in that case. How do we
|
||||
display this result with three digits? We will use a *menu* for that. Menus are
|
||||
an essential component of the DB48X user interface.
|
||||
|
||||
Let us type 🟨 _O_ (_Disp_). This shows the `DisplayModesMenu`. The menu
|
||||
occupies three rows at the bottom of the screen, with six columns. Menus can
|
||||
give a quick access to 18 functions directly, six more with a single shift 🟨,
|
||||
and yet another six with the second shift 🟦. Hitting the shift key 🟨
|
||||
repeatedly will highlight the different rows of the menu.
|
||||
|
||||
On the lower row of the menu, the second entry from the left is labeled `Fix`.
|
||||
The `Fix` display mode shows a fixed number of digits after the decimal
|
||||
separator. There are other modes, `Sci` to display in scientific notation, `Eng`
|
||||
to display with engineering multiples (the exponent is a multiple of three), and
|
||||
`Sig` to display at most a given number of digits.
|
||||
|
||||
We can type _3_, _F2_, where _F2_ is the second key from the left on the top row
|
||||
of the keyboard. This activates the `Fix 3` mode, which shows three digits after
|
||||
the decimal separator. The display changes to `0.868` for the answer to the
|
||||
first question, and `6.892 °` for the answer to the second question.
|
||||
|
||||
|
||||
## Displaying the on-line help for a function
|
||||
|
||||
Since the number of available commands in DB48X is quite high, it is useful to
|
||||
be able to consult the built-in help. In order to get help on a command, simply
|
||||
hold the corresponding key until the help shows up. For instance, to get
|
||||
[help about the command](#std) under the `Std` label, simply hold the _F1_ key.
|
||||
|
||||
This also works for normal keyboard operations. For instance, if you hold the
|
||||
_SIN_ key, you will get the [help about the sine command](#sin).
|
||||
|
||||
|
||||
## Complex number operations
|
||||
|
||||
**Installing the DB48X program file**
|
||||
|
||||
|
||||
## Switching between DM42 and DB48X
|
||||
|
|
|
|||
150
help/db50x.md
150
help/db50x.md
|
|
@ -939,23 +939,155 @@ DB50X, and show you how to use it efficiently.
|
|||
[](https://www.youtube.com/watch?v=rVWy4N0lBOI&list=PLz1qkflzABy-Cs1R07zGB8A9K5Yjolmlf)
|
||||
|
||||
|
||||
## Installation process
|
||||
## Arithmetic operations
|
||||
|
||||
**Downloading the software**
|
||||
Let's compute the area of a room made of a main section that is 6 meters by 8.3
|
||||
meters, with an additional smaller section that is 3.5 meters by 2.8.
|
||||
|
||||
**Connecting the calculator to a computer**
|
||||
A first way to do it is to use the reverse polish stack-based approach, by
|
||||
typing the following sequence of keys: _6_, _ENTER_, _8_, _._, _3_, _×_, _3_,
|
||||
_._, _5_, _ENTER_, _2_, _._, _8_, _×_, _+_. The result, `59.6`, shows on the
|
||||
stack. Prior to pressing the _+_ key, the intermediate results for the two
|
||||
multiplications, `49.8` and `9.8`, could be seen on the stack.
|
||||
|
||||
**Setup menu system (firmware menus)**
|
||||
RPL also supports the standard algebraic notation. Begin the computation with
|
||||
the _'()_ key. The editor contains quotes, `''` with the cursor between
|
||||
them. The cursor shows the latter `A`, indicating algebraic entry. Type _6_,
|
||||
_×_, _8_, _._, _3_, _+_, _3_, _._, _5_, _×_, _2_, _._, _8_. At this point,
|
||||
the text editor should show the whole expression, `'6·8.3+3.5·2.8'`
|
||||
or `'6×8.3+3.5×2.8'`. Press `ENTER` and the expression shows up on the
|
||||
stack. Hitting the _=_ / _EVAL_ / _SPC_ key (located between the _._ and _+_
|
||||
keys) evaluates the expression, to get the result `59.6`.
|
||||
|
||||
**Exposing internal storage as a USB disk**
|
||||
Algebraic and reverse-polish computations are equivalent, and can be mixed and
|
||||
matched during computations. Using one or the other is stricly a matter of
|
||||
preference. Algebraic data entry makes it easier to view the entire
|
||||
expression. Reverse-polish makes it easier to see intermediate results.
|
||||
|
||||
**Copying DB50X installation files**
|
||||
|
||||
**Copying DM32 installation files**
|
||||
## Fractions
|
||||
|
||||
**Installing the DB50X QSPI file**
|
||||
Let us now compute how many pies we need to feed 22 kids if we divide each pie
|
||||
in 8 slices. Using the RPL approach, we would type _2_, _2_, _ENTER_, _8_,
|
||||
_÷_. Using the algebraic notation, we would type _'()_, _2_, _2_, _÷_, _8_,
|
||||
_ENTER_ and then use the _=_ to perform the computation.
|
||||
|
||||
With the default settings, you should see a mixed fraction, `2 ³/₄`. Unlike many
|
||||
calculators, DB50X by default perform exact computations on fractions instead of
|
||||
using approximate decimal numbers.
|
||||
|
||||
You can convert that fraction to a decimal value and back using the `Cycle`
|
||||
command, which is bound to the _EEX_ key. A first press will show `2.75`, and a
|
||||
second press will show the value again as fraction `2 ³/₄`.
|
||||
|
||||
|
||||
## Mathematical functions
|
||||
|
||||
DB50X features a number of mathematical functions. Some of the functions are
|
||||
directly available on the keyboard.
|
||||
|
||||
We can compute the length of the diagonal of a rectangle with sides 2m and 3m
|
||||
using the Pythagorean theorem, and display it in millimeters.
|
||||
|
||||
In RPL, we can type the following sequence: _2_, _x²_ (🟨 _C_), _3_, _x²_,
|
||||
_+_, _√x_ (_C_), _1_, _0_, _0_, _0_, _×_. The decimal result,
|
||||
`3 605.55127 546`, is shown on the stack. The digits in the whole part of the
|
||||
decimal number are grouped 3 by 3, while the digits in the fractional part are
|
||||
grouped 5 by 5.
|
||||
|
||||
In algebraic mode, we can type the following sequence:
|
||||
_'()_, _1_, _0_, _0_, _0_, _×_, _√x_,
|
||||
_2_, _x²_ (🟨 _C_), _+_, _3_, _x²_, _ENTER_. The mathematical
|
||||
expresssion shows up on the stack graphically. It can then be evaluated using
|
||||
the _=_ key, and shows the same result as for RPL mode.
|
||||
|
||||
|
||||
## Mixing algebraic and reverse-polish operations
|
||||
|
||||
In the algebraic expression, we have multiplied by 1000 first, whereas in the
|
||||
RPL case, we multiplied by 1000 last. We can also multiply by 1000 last in
|
||||
algebraic mode. There are at least two ways to do it.
|
||||
|
||||
A first method is to use the arrow key to exit the parentheses around the
|
||||
argument of the square root function, as follows: _'()_, _√x_,
|
||||
_2_, _x²_, _+_, _3_, _x²_, _▶︎_, _×_, _1_, _0_, _0_, _0_,
|
||||
_ENTER_. The expression with the multiplication is then shown on the stack, and
|
||||
can then be evaluated with the _=_ key.
|
||||
|
||||
A second method is to mix and match algebraic and RPL, by typing
|
||||
the following sequence: _'()_, _√x_, _2_, _x²_, _+_,
|
||||
_3_, _x²_, _ENTER_. At this point, the expression without the
|
||||
multiplication is on the stack. We can then multiply it by 1000 by typing
|
||||
_1_, _0_, _0_, _0_, _×_. The expression with the multiplication is then shown on
|
||||
the stack, and can then be evaluated with the _=_ key.
|
||||
|
||||
|
||||
## Trigonometric functions
|
||||
|
||||
Consider that we need to build a plank ramp. We can ask a number of questions,
|
||||
like:
|
||||
|
||||
* If the plank is 5 meters in length, and the slope is 10 degrees, how high
|
||||
will it reach?
|
||||
|
||||
* If we need to reach 60 cm above ground, what is the required slope?
|
||||
|
||||
In RPL, can answer the first question by typing _1_, _0_, _SIN_, _5_,
|
||||
_×_. The result is shown in scientific format as `8.68240 88833 5×₁₀⁻¹`.
|
||||
In algebraic mode, we would type _'()_, _5_, _×_, _SIN_, _1_, _0_, _ENTER_
|
||||
and then evaluating the expression with _=_. This shows the same result.
|
||||
|
||||
We can answer the second question using RPL by typing _6_, _0_, _ENTER_, _5_,
|
||||
_ENTER_, _1_, _0_, _0_, _×_, _÷_, _sin⁻¹_ (🟨 _J_). The result is shown as
|
||||
`6.89210 25793 5 °`. This is an example of *unit object*: the value is
|
||||
associated with a unit, in that case the `°` symbol indicating that we use
|
||||
degrees. DB50X supports three other angle modes, radians, grads and fractions of
|
||||
pi (piradians).
|
||||
|
||||
Answering the same question using algebraic mode introduces a new little
|
||||
keyboard trick. Type _'()_, _sin⁻¹_, _6_, _0_, _÷_, _'()_,
|
||||
_5_, _×_, _1_, _0_, _0_, _ENTER_, and then evaluating the expression with the
|
||||
_=_ key. Observe how the second use of the _'()_ key, which inserts parentheses
|
||||
when used inside an expression.
|
||||
|
||||
|
||||
## Selecting display modes
|
||||
|
||||
The scientific notation may not be the most readable in that case. How do we
|
||||
display this result with three digits? We will use a *menu* for that. Menus are
|
||||
an essential component of the DB50X user interface.
|
||||
|
||||
Let us type 🟨 _O_ (_Disp_). This shows the `DisplayModesMenu`. The menu
|
||||
occupies three rows at the bottom of the screen, with six columns. Menus can
|
||||
give a quick access to 18 functions directly, six more with a single shift 🟨,
|
||||
and yet another six with the second shift 🟦. Hitting the shift key 🟨
|
||||
repeatedly will highlight the different rows of the menu.
|
||||
|
||||
On the lower row of the menu, the second entry from the left is labeled `Fix`.
|
||||
The `Fix` display mode shows a fixed number of digits after the decimal
|
||||
separator. There are other modes, `Sci` to display in scientific notation, `Eng`
|
||||
to display with engineering multiples (the exponent is a multiple of three), and
|
||||
`Sig` to display at most a given number of digits.
|
||||
|
||||
We can type _3_, _F2_, where _F2_ is the second key from the left on the top row
|
||||
of the keyboard. This activates the `Fix 3` mode, which shows three digits after
|
||||
the decimal separator. The display changes to `0.868` for the answer to the
|
||||
first question, and `6.892 °` for the answer to the second question.
|
||||
|
||||
|
||||
## Displaying the on-line help for a function
|
||||
|
||||
Since the number of available commands in DB50X is quite high, it is useful to
|
||||
be able to consult the built-in help. In order to get help on a command, simply
|
||||
hold the corresponding key until the help shows up. For instance, to get
|
||||
[help about the command](#std) under the `Std` label, simply hold the _F1_ key.
|
||||
|
||||
This also works for normal keyboard operations. For instance, if you hold the
|
||||
_SIN_ key, you will get the [help about the sine command](#sin).
|
||||
|
||||
|
||||
## Complex number operations
|
||||
|
||||
**Installing the DB50X program file**
|
||||
|
||||
|
||||
## Switching between DM32 and DB50X
|
||||
|
|
|
|||
Loading…
Reference in a new issue