- kbhit() test is working and returns a character.

- fine tuned the veralayers.c demonstration program.
- fine tuned clearline(), which will clear the current line of conio_cursor_y and reposition x at the start of the line.

src/main/fragment/cache/fragment-cache-wdc65c02.asm

@@ -2191,3 +2191,127 @@ sta {c1}
 tya
 and {c1}
 sta {c1}
+//FRAGMENT vbuz1=_bnot_vbuz2
+lda {z2}
+eor #$ff
+sta {z1}
+//FRAGMENT vbuz1=_bnot_vbuaa
+eor #$ff
+sta {z1}
+//FRAGMENT vbuz1=_bnot_vbuxx
+txa
+eor #$ff
+sta {z1}
+//FRAGMENT vbuz1=_bnot_vbuyy
+tya
+eor #$ff
+sta {z1}
+//FRAGMENT vbuaa=_bnot_vbuz1
+lda {z1}
+eor #$ff
+//FRAGMENT vbuaa=_bnot_vbuaa
+eor #$ff
+//FRAGMENT vbuaa=_bnot_vbuxx
+txa
+eor #$ff
+//FRAGMENT vbuaa=_bnot_vbuyy
+tya
+eor #$ff
+//FRAGMENT vbuxx=_bnot_vbuz1
+lda {z1}
+eor #$ff
+tax
+//FRAGMENT vbuxx=_bnot_vbuaa
+eor #$ff
+tax
+//FRAGMENT vbuxx=_bnot_vbuxx
+txa
+eor #$ff
+tax
+//FRAGMENT vbuxx=_bnot_vbuyy
+tya
+eor #$ff
+tax
+//FRAGMENT vbuyy=_bnot_vbuz1
+lda {z1}
+eor #$ff
+tay
+//FRAGMENT vbuyy=_bnot_vbuaa
+eor #$ff
+tay
+//FRAGMENT vbuyy=_bnot_vbuxx
+txa
+eor #$ff
+tay
+//FRAGMENT vbuyy=_bnot_vbuyy
+tya
+eor #$ff
+tay
+//FRAGMENT vbuc1_lt_vbuz1_then_la1
+lda #{c1}
+cmp {z1}
+bcc {la1}
+//FRAGMENT vbuz1=pbuz2_derefidx_vbuz3
+ldy {z3}
+lda ({z2}),y
+sta {z1}
+//FRAGMENT vbuaa=pbuz1_derefidx_vbuz2
+ldy {z2}
+lda ({z1}),y
+//FRAGMENT vbuxx=pbuz1_derefidx_vbuz2
+ldy {z2}
+lda ({z1}),y
+tax
+//FRAGMENT vbuyy=pbuz1_derefidx_vbuz2
+ldy {z2}
+lda ({z1}),y
+tay
+//FRAGMENT vbuz1=pbuz2_derefidx_vbuaa
+tay
+lda ({z2}),y
+sta {z1}
+//FRAGMENT vbuaa=pbuz1_derefidx_vbuaa
+tay
+lda ({z1}),y
+//FRAGMENT vbuxx=pbuz1_derefidx_vbuaa
+tay
+lda ({z1}),y
+tax
+//FRAGMENT vbuyy=pbuz1_derefidx_vbuaa
+tay
+lda ({z1}),y
+tay
+//FRAGMENT vbuz1=pbuz2_derefidx_vbuxx
+txa
+tay
+lda ({z2}),y
+sta {z1}
+//FRAGMENT vbuaa=pbuz1_derefidx_vbuxx
+txa
+tay
+lda ({z1}),y
+//FRAGMENT vbuxx=pbuz1_derefidx_vbuxx
+txa
+tay
+lda ({z1}),y
+tax
+//FRAGMENT vbuyy=pbuz1_derefidx_vbuxx
+txa
+tay
+lda ({z1}),y
+tay
+//FRAGMENT vbuz1=pbuz2_derefidx_vbuyy
+lda ({z2}),y
+sta {z1}
+//FRAGMENT vbuaa=pbuz1_derefidx_vbuyy
+lda ({z1}),y
+//FRAGMENT vbuxx=pbuz1_derefidx_vbuyy
+lda ({z1}),y
+tax
+//FRAGMENT vbuyy=pbuz1_derefidx_vbuyy
+lda ({z1}),y
+tay
+//FRAGMENT vwuz1=_word_vbuaa
+sta {z1}
+lda #0
+sta {z1}+1

src/main/kc/lib/conio-cx16.c

@@ -45,12 +45,46 @@ void conio_x16_init() {
 
 // Return true if there's a key waiting, return false if not
 unsigned char kbhit(void) {
-    // CIA#1 Port A: keyboard matrix columns and joystick #2
+
-    char* const CIA1_PORT_A = 0xdc00;
+    char ch = 0;
-    // CIA#1 Port B: keyboard matrix rows and joystick #1.
+    char* chptr = &ch;
-    char* const CIA1_PORT_B = 0xdc01;
+
-    *CIA1_PORT_A = 0;
+    char* IN_DEV = $028A;        // Current input device number
-    return ~*CIA1_PORT_B;
+    char* GETIN  = $FFE4;        // CBM GETIN API
+
+    kickasm(uses chptr, uses IN_DEV, uses GETIN) {{
+
+        jsr _kbhit
+        bne L3
+
+        jmp continue1
+
+        .var via1 = $9f60                  //VIA#1
+        .var d1pra = via1+1
+
+    _kbhit:
+        ldy     d1pra       // The count of keys pressed is stored in RAM bank 0.
+        stz     d1pra       // Set d1pra to zero to access RAM bank 0.
+        lda     $A00A       // Get number of characters from this address in the ROM of the CX16 (ROM 38).
+        sty     d1pra       // Set d1pra to previous value.
+        rts
+
+    L3:
+        ldy     IN_DEV          // Save current input device
+        stz     IN_DEV          // Keyboard
+        phy
+        jsr     GETIN           // Read char, and return in .A
+        ply
+        sta     chptr           // Store the character read in ch
+        sty     IN_DEV          // Restore input device
+        ldx     #>$0000
+        rts
+
+    continue1:
+        nop
+     }}
+
+    return ch;
 }
 
 // Set the color for the background. The old color setting is returned.
@@ -283,10 +317,12 @@ void cputln() {
 
 void clearline() {
     // Select DATA0
+    unsigned byte* conio_addr = CONIO_SCREEN_TEXT;
+    conio_addr += conio_cursor_y*256;
     *VERA_CTRL &= ~VERA_ADDRSEL;
     // Set address
-    *VERA_ADDRX_L = <conio_line_text;
+    *VERA_ADDRX_L = <conio_addr;
-    *VERA_ADDRX_M = >conio_line_text;
+    *VERA_ADDRX_M = >conio_addr;
     *VERA_ADDRX_H = VERA_INC_1;
     char color = ( conio_backcolor << 4 ) | conio_textcolor;
     for( unsigned int c=0;c<CONIO_WIDTH; c++ ) {
@@ -294,6 +330,7 @@ void clearline() {
         *VERA_DATA0 = ' ';
         *VERA_DATA0 = color;
     }
+    conio_cursor_x = 0;
 }
 
 // Insert a new line, and scroll the lower part of the screen down.

src/test/kc/examples/cx16/veralayers.c

@@ -1,53 +1,99 @@
 #include <printf.h>
 
 void main() {
-    textcolor(BLUE);
+
+    textcolor(WHITE);
     backcolor(BLACK);
     clrscr();
-    // This statement sets the base of the display layer 1 at VRAM address 0x0200
+
-    setscreenlayermapbase(0,0x20);
+
-    screenlayer(0);
-    clrscr();
     screenlayer(1);
 
-    gotoxy(0,0);
-
     gotoxy(0,16);
-    textcolor(RED);
-    unsigned int width = screensizex();
-    unsigned int height = screensizey();
-    printf("vera card width = %u; height = %u\n", width, height);
-
-    printf("dc video = %x\n", *VERA_DC_VIDEO);
-    printf("vera card layer 0 enabled = %x\n", screenlayerenabled(0));
-    printf("vera card mapbase layer 0 = %x\n", getscreenlayermapbase(0));
-    printf("l0 config = %x\n", *VERA_L0_CONFIG);
-    printf("l0 tilebase = %x\n", *VERA_L0_TILEBASE);
-    printf("l0 vscroll l = %x\n", *VERA_L0_HSCROLL_L);
-    printf("l0 vscroll h = %x\n", *VERA_L0_HSCROLL_H);
-    printf("vera card layer 1 enabled = %x\n", screenlayerenabled(1));
-    printf("vera card mapbase layer 1 = %x\n", getscreenlayermapbase(1));
-    printf("l1 config = %x\n", *VERA_L1_CONFIG);
-    printf("l1 tilebase = %x\n", *VERA_L1_TILEBASE);
-    printf("l1 vscroll l = %x\n", *VERA_L1_HSCROLL_L);
-    printf("l1 vscroll h = %x\n", *VERA_L1_HSCROLL_H);
-
-    textcolor(BLUE);
-    //disablescreenlayer1();
-    screenlayerenable(0);
-    printf("dc video = %x\n", *VERA_DC_VIDEO);
-    printf("vera card layer 0 enabled = %x\n", screenlayerenabled(0));
-    printf("vera card layer 1 enabled = %x\n", screenlayerenabled(1));
-    printf("vera card mapbase layer 0 = %x\n", getscreenlayermapbase(0));
-    printf("vera card mapbase layer 1 = %x\n", getscreenlayermapbase(1));
-    printf("vera card mapbase layer 1 = %x\n", getscreenlayermapbase(1));
-
-    screenlayer(0);
-    gotoxy(0,0);
     textcolor(GREEN);
+
+    printf("this program demonstrates the layer functionality in text mode.\n");
+
+    // Here we use the screensizex and screensizey functions to show the width and height of the text screen.
+    printf("vera card width = %u; height = %u\n", screensizex(), screensizey());
+
+    // This is the content of the main controller registers of the VERA of layer 1.
+    // Layer 1 is the default layer that is activated in the CX16 at startup.
+    // It displays the characters in 1BPP 16x16 color mode!
+    printf("vera dc video = %x\n", *VERA_DC_VIDEO);
+    printf("vera layer 1 config = %x\n", *VERA_L1_CONFIG);
+    printf("vera layer 1 enabled = %x\n", screenlayerenabled(1));
+    printf("vera layer 1 mapbase = %x, tilebase = %x\n", getscreenlayermapbase(1), *VERA_L1_TILEBASE);
+    printf("vera layer 1 vscroll high = %x, low = %x\n", *VERA_L1_HSCROLL_H, *VERA_L1_HSCROLL_L);
+
+    // Wait for a keypress and after clear the line!
+    textcolor(YELLOW);
+    printf("press a key");
+    while(!kbhit());
+    clearline();
+
+    // Now we continue with demonstrating the layering!
+    // We set the mapbase of layer 0 to an address in VRAM.
+    // We copy the tilebase address from layer 1, so that we reference to the same tilebase.
+    // We print a text on layer 0, which of course, won't yet be displayed,
+    // because we haven't activated layer 0 on the VERA.
+    // But the text will be printed and awaiting to be displayer later, once we activate layer 0!
+    // But first, we also print the layer 0 VERA configuration.
+    // This statement sets the base of the display layer 1 at VRAM address 0x0200
+
+    setscreenlayermapbase(0,0x20); // Set the map base to address 0x04000
     *VERA_L0_CONFIG = *VERA_L1_CONFIG;
     *VERA_L0_TILEBASE = *VERA_L1_TILEBASE;
-    printf("this is printed on layer 0");
 
-    //screenlayerdisable(0);
+    printf("vera dc video = %x\n", *VERA_DC_VIDEO);
+    printf("vera layer 0 config = %x\n", *VERA_L0_CONFIG);
+    printf("vera layer 0 enabled = %x\n", screenlayerenabled(0));
+    printf("vera layer 0 mapbase = %x, tilebase = %x\n", getscreenlayermapbase(0), *VERA_L0_TILEBASE);
+    printf("vera layer 0 vscroll high = %x, low = %x\n", *VERA_L0_HSCROLL_H, *VERA_L0_HSCROLL_L);
+
+    // Now we print the layer 0 text on the layer 0!
+    screenlayer(0); // We set conio to output to layer 0 instead of layer 1!
+    clrscr(); // We clear the screen of layer 0!
+    textcolor(BLUE);
+    backcolor(WHITE);
+    gotoxy(19,4);
+    printf("                                        ");
+    gotoxy(19,5);
+    printf("     this is printed on layer 0 !!!     ");
+    gotoxy(19,6);
+    printf("                                        ");
+
+    gotoxy(0,40);
+
+    screenlayer(1); // Now we ask conio again to output to layer 1!
+
+    // Wait for a keypress and after clear the line!
+    textcolor(YELLOW);
+    backcolor(BLACK);
+    printf("press a key to show layer 0 and show the text!");
+    while(!kbhit());
+    clearline();
+
+
+    // Now we activate layer 0.
+    screenlayerenable(0);
+
+    // Wait for a keypress and after clear the line!
+    textcolor(YELLOW);
+    backcolor(BLACK);
+    printf("press a key to hide layer 0 and hide the text again");
+    while(!kbhit());
+    clearline();
+
+    screenlayerdisable(0);
+
+    clrscr();
+    textcolor(RED);
+    backcolor(WHITE);
+    gotoxy(19,10);
+    printf("                                     ");
+    gotoxy(19,11);
+    printf("     analyze the code and learn!     ");
+    gotoxy(19,12);
+    printf("                                     ");
 }