Chars (PI5)e - Versionsgeschichte

Satyria: /* The ANSI Character Code */

2025-02-22T10:32:21Z

The ANSI Character Code

← Nächstältere Version		Version vom 22. Februar 2025, 11:32 Uhr
Zeile 13:		Zeile 13:
	! !! !! !! !! !! !! !! !! !! !! !! !! !! !! !! !!		! !! !! !! !! !! !! !! !! !! !! !! !! !! !! !! !!
	\|-		\|-
	! !! 00 !! 01 !! 02 !! 03 !! 04 !! 05 !! 06 !! 07 !! 08 !! 09 !! 0A !! 0B !! 0C !! 0D !! 0E !! 0F		! !! 0x0 !! 0x1 !! 0x2 !! 0x3 !! 0x4 !! 0x5 !! 0x6 !! 0x7 !! 0x8 !! 0x9 !! 0xA !! 0xB !! 0xC !! 0xD !! 0xE !! 0xF
	\|-		\|-
	! 0x0		! 0x0
Zeile 63:		Zeile 63:
	\| ≡ \|\| ± \|\| ≥ \|\| ≤ \|\| ⌠ \|\| ⌡ \|\| ÷ \|\| ≈ \|\| ° \|\| • \|\| · \|\| √ \|\| ⁿ \|\| ² \|\| ■ \|\|		\| ≡ \|\| ± \|\| ≥ \|\| ≤ \|\| ⌠ \|\| ⌡ \|\| ÷ \|\| ≈ \|\| ° \|\| • \|\| · \|\| √ \|\| ⁿ \|\| ² \|\| ■ \|\|
	\|}		\|}


	== Creating a Font ==		== Creating a Font ==

Satyria: /* Testing the Function */

2024-08-23T10:51:40Z

Testing the Function

← Nächstältere Version		Version vom 23. August 2024, 11:51 Uhr
Zeile 346:		Zeile 346:

	You can download the source code as a ZIP file from the following link: https://www.satyria.de/arm/sources/assem/chars.zip		You can download the source code as a ZIP file from the following link: https://www.satyria.de/arm/sources/assem/chars.zip
	{\|
	\|-		-----
	\| style="width: 33%; ~~text-align~~:~~left~~;" \| [[Graphics (PI5)\|< Back]] \|\| style="width: 33%" \|[[English\|^ Home]] \|\| style="width: 33%; text-align:right;" \| Next >
			{\| style="width: 100%;
			\| style="width: 33%;" \| [[Graphics (PI5)\|< Back (Graphics (PI5))]]
			\| style="width: 33%; text-align:center;" \| [[English\|< Home >]]
			\| style="width: 33%; text-align:right;" \| [[The Terminal\|Next (The Terminal) >]]
	\|}		\|}

Satyria: /* Testing the Function */

2024-08-22T07:30:12Z

Testing the Function

← Nächstältere Version		Version vom 22. August 2024, 08:30 Uhr
Zeile 346:		Zeile 346:

	You can download the source code as a ZIP file from the following link: https://www.satyria.de/arm/sources/assem/chars.zip		You can download the source code as a ZIP file from the following link: https://www.satyria.de/arm/sources/assem/chars.zip
			{\|
			\|-
			\| style="width: 33%; text-align:left;" \| [[Graphics (PI5)\|< Back]] \|\| style="width: 33%" \|[[English\|^ Home]] \|\| style="width: 33%; text-align:right;" \| Next >
			\|}

Satyria: /* Testing the Function */

2024-08-19T19:18:53Z

Testing the Function

← Nächstältere Version		Version vom 19. August 2024, 20:18 Uhr
Zeile 345:		Zeile 345:
	In this example, we turn off the LED, initialize the screen, and then draw a series of characters on the screen starting at position (100, 100). With each iteration of the loop, the character is moved 10 pixels down. If the program runs successfully, error code 2 is output.		In this example, we turn off the LED, initialize the screen, and then draw a series of characters on the screen starting at position (100, 100). With each iteration of the loop, the character is moved 10 pixels down. If the program runs successfully, error code 2 is output.

	You can download the source code as a ZIP file from the following link: [https://www.satyria.de/arm/sources/assem/chars.zip]		You can download the source code as a ZIP file from the following link: https://www.satyria.de/arm/sources/assem/chars.zip

Satyria am 19. August 2024 um 19:18 Uhr

2024-08-19T19:18:01Z

← Nächstältere Version		Version vom 19. August 2024, 20:18 Uhr
Zeile 344:		Zeile 344:

	In this example, we turn off the LED, initialize the screen, and then draw a series of characters on the screen starting at position (100, 100). With each iteration of the loop, the character is moved 10 pixels down. If the program runs successfully, error code 2 is output.		In this example, we turn off the LED, initialize the screen, and then draw a series of characters on the screen starting at position (100, 100). With each iteration of the loop, the character is moved 10 pixels down. If the program runs successfully, error code 2 is output.

			You can download the source code as a ZIP file from the following link: [https://www.satyria.de/arm/sources/assem/chars.zip]

Satyria: /* Drawing Characters on the Screen */

2024-08-13T11:20:57Z

Drawing Characters on the Screen

← Nächstältere Version		Version vom 13. August 2024, 12:20 Uhr
Zeile 169:		Zeile 169:
	// Check the bit using the following formula:		// Check the bit using the following formula:
	// (Row >> (7 - BitPos)) & 1;		// (Row >> (7 - BitPos)) & 1;
	ldrb w13, [x10,		ldrb w13, [x10, w11]

	w11]
	ldr w14, =7		ldr w14, =7
	sub w14, w14, w12		sub w14, w14, w12
Zeile 179:		Zeile 177:
	</syntaxhighlight>		</syntaxhighlight>

	If the ~~bit~~ is ~~set~~, we ~~calculate~~ the ~~corresponding coordinates on~~ the ~~screen and call the `SetPixel` function to set the pixel at that position~~:		If the result is 0, we draw a pixel in the background color; otherwise, in the foreground color.:

	<syntaxhighlight lang="asm">		<syntaxhighlight lang="asm">
	// ~~Draw~~ the ~~pixel~~		// If the result is 0, draw in the background color
	~~add~~ w13, ~~w20~~, ~~w12~~		cbz w13, 5f
	~~add w14~~, ~~w21~~, ~~w11~~
	~~bl SetPixel~~		// Otherwise, draw in the foreground color
			ldr x13, =FrontColor
			ldr w13, [x13]
			ldr x14, =DrawColor
			str w13, [x14]
			b 6f

	5:		5:
			ldr x13, =BackColor
			ldr w13, [x13]
			ldr x14, =DrawColor
			str w13, [x14]
	</syntaxhighlight>		</syntaxhighlight>

	~~This process is repeated for every row of the character. After each row is completed~~, the ~~function loops back and moves to~~ the ~~next row. Once all rows are drawn,~~ the ~~function exits~~:		Finally, we draw the pixel at the calculated position on the screen:

	<syntaxhighlight lang="asm">		<syntaxhighlight lang="asm">
	// ~~Jump back to~~ the ~~inner loop~~		6:
			// Draw the pixel at the position
			mov w0, w12
			add w0, w0, w20
			mov w1, w11
			add w1, w1, w21
			bl DrawPixel

			// end_for w12
	add w12, w12, #1		add w12, w12, #1
	b 3b		b 3b
	4:		4:
	// ~~Jump back to the outer loop~~		// end_for w11
	add w11, w11, #1		add w11, w11, #1
	b 1b		b 1b
	2:		2:
	~~</syntaxhighlight>~~

	~~Finally, we restore the saved values and return:~~

	~~<syntaxhighlight lang="asm">~~
	ldp x14, x15, [sp], 16		ldp x14, x15, [sp], 16
	ldp x12, x13, [sp], 16		ldp x12, x13, [sp], 16
Zeile 212:		Zeile 223:
	ret		ret
	</syntaxhighlight>		</syntaxhighlight>

	~~This is how the `DrawChar` function draws a character on the screen.~~

	Here is the entire code for the `DrawChar` function:		Here is the entire code for the `DrawChar` function:

Satyria: /* Drawing Characters on the Screen */

2024-08-13T11:05:43Z

Drawing Characters on the Screen

← Nächstältere Version		Version vom 13. August 2024, 12:05 Uhr
Zeile 297:		Zeile 297:
	</syntaxhighlight>		</syntaxhighlight>

	Testing the Function		== Testing the Function ==

	To test the function, we modify our main program to include a loop that writes a series of characters to the screen:		To test the function, we modify our main program to include a loop that writes a series of characters to the screen:

Satyria am 13. August 2024 um 10:38 Uhr

2024-08-13T10:38:28Z

← Nächstältere Version		Version vom 13. August 2024, 11:38 Uhr
Zeile 214:		Zeile 214:

	This is how the `DrawChar` function draws a character on the screen.		This is how the `DrawChar` function draws a character on the screen.

			Here is the entire code for the `DrawChar` function:

			<syntaxhighlight lang="asm">
			// void DrawChar(char c, u32 x0, u32 y0)
			// Draws a character at position x0, y0 on the screen
			.globl DrawChar
			DrawChar:
			stp x29, x30, [sp, -16]!
			stp x20, x21, [sp, -16]!
			stp x10, x11, [sp, -16]!
			stp x12, x13, [sp, -16]!
			stp x14, x15, [sp, -16]!
			mov x29, sp

			// First, save the position
			mov w20, w1 // x0
			mov w21, w2 // y0

			// Calculate the pointer to the correct character
			ldr x10, =font
			lsl w0, w0, #3
			add x10, x10, x0

			// for (w11 = 0; w11 < FONT_HEIGHT; w11++)
			mov w11, #0
			1:
			cmp w11, #FONT_HEIGHT
			bge 2f

			// for (w12 = 0; w12 < FONT_WIDTH; w12++)
			mov w12, #0
			3:
			cmp w12, #FONT_WIDTH
			bge 4f

			// Check the bit using the following formula:
			// (Row >> (7 - BitPos)) & 1;
			ldrb w13, [x10, x11]
			mov w14, #7
			sub w14, w14, w12
			lsr w13, w13, w14
			and w13, w13, #1
			// If the result is 0, then draw the background
			cbz w13, 5f

			// Otherwise, draw in the foreground color
			ldr x13, =FrontColor
			ldr w13, [x13]
			ldr x14, =DrawColor
			str w13, [x14]
			b 6f

			5:
			ldr x13, =BackColor
			ldr w13, [x13]
			ldr x14, =DrawColor
			str w13, [x14]

			6:
			// Draw the pixel at the position
			mov w0, w12
			add w0, w0, w20
			mov w1, w11
			add w1, w1, w21
			bl DrawPixel

			// end_for w12
			add w12, w12, #1
			b 3b
			4:
			// end_for w11
			add w11, w11, #1
			b 1b
			2:
			ldp x14, x15, [sp], 16
			ldp x12, x13, [sp], 16
			ldp x10, x11, [sp], 16
			ldp x20, x21, [sp], 16
			ldp x29, x30, [sp], 16
			ret
			</syntaxhighlight>

			Testing the Function

			To test the function, we modify our main program to include a loop that writes a series of characters to the screen:

			<syntaxhighlight lang="asm">
			//
			// kernel.S
			//

			.section .text
			.globl main
			main:

			bl LED_off
			bl Init_Screen

			mov w10, #33
			mov w11, #100
			2:
			cmp w10, #90
			bge 1f

			mov w0, w10
			mov w1, #100
			mov w2, w11
			bl DrawChar
			add w11, w11, #10
			add w10, w10, #1

			b 2b
			1:
			mov w0, #2
			bl LED_Error
			999:
			b 999b
			</syntaxhighlight>

			In this example, we turn off the LED, initialize the screen, and then draw a series of characters on the screen starting at position (100, 100). With each iteration of the loop, the character is moved 10 pixels down. If the program runs successfully, error code 2 is output.

Satyria am 13. August 2024 um 10:33 Uhr

2024-08-13T10:33:26Z

Änderungen zeigen

Satyria am 13. August 2024 um 10:25 Uhr

2024-08-13T10:25:55Z

← Nächstältere Version		Version vom 13. August 2024, 11:25 Uhr
Zeile 1:		Zeile 1:
	~~Here is the English translation of the text with content verification:~~		== Drawing Characters on the Raspberry Pi ==

	~~---~~

	Drawing Characters on the Raspberry Pi

	After implementing a function to set individual pixels, we now want to teach the Raspberry Pi to display text on the screen. Texts consist of characters that the computer does not inherently recognize. Like a human, the computer must first "learn" how each character looks before it can display it. These characters are defined in a specific code that the computer understands. One of the most widely used codes is the ANSI character code.		After implementing a function to set individual pixels, we now want to teach the Raspberry Pi to display text on the screen. Texts consist of characters that the computer does not inherently recognize. Like a human, the computer must first "learn" how each character looks before it can display it. These characters are defined in a specific code that the computer understands. One of the most widely used codes is the ANSI character code.