From 06f240dd6dd5f6eaaf934c6a4d765a69a3c2b383 Mon Sep 17 00:00:00 2001
From: giomba <giomba@glgprograms.it>
Date: Fri, 13 Oct 2023 09:08:22 +0200
Subject: [PATCH] Mix C and assembly, minor modifications to print routines.

---
 Makefile                             |  3 ++-
 src/ceda_print.h                     |  5 +++--
 src/ceda_print_a.asm                 | 26 ++++++++++++++++++++++++++
 src/{ceda_print.c => ceda_print_c.c} |  0
 src/main.c                           |  1 +
 5 files changed, 32 insertions(+), 3 deletions(-)
 create mode 100644 src/ceda_print_a.asm
 rename src/{ceda_print.c => ceda_print_c.c} (100%)

diff --git a/Makefile b/Makefile
index 94d36b5..7eacd99 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,8 @@
 PROJECT := demo
 
 SRC = \
-	  src/ceda_print.c		\
+	  src/ceda_print_a.asm	\
+	  src/ceda_print_c.c	\
 	  src/main.c 			\
 	  \
 
diff --git a/src/ceda_print.h b/src/ceda_print.h
index b2c7767..ca08a5e 100644
--- a/src/ceda_print.h
+++ b/src/ceda_print.h
@@ -1,7 +1,8 @@
 #ifndef CEDA_PRINT_H
 #define CEDA_PRINT_H
 
-void ceda_print(const char* s);
+void ceda_cls(void);
+
+void ceda_print(const char *s);
 
 #endif // CEDA_PRINT_H
-
diff --git a/src/ceda_print_a.asm b/src/ceda_print_a.asm
new file mode 100644
index 0000000..3e14e15
--- /dev/null
+++ b/src/ceda_print_a.asm
@@ -0,0 +1,26 @@
+SECTION code
+PUBLIC _ceda_cls
+
+_ceda_cls:
+    push    af
+    push    bc
+    push    de
+    push    hl
+
+    ld      hl,$d000
+    ld      de,2000
+    ld      c,$20
+_ceda_cls_loop:
+    ld      (hl),c
+    inc     hl
+    dec     de
+    ld      a,d
+    or      e
+    jp      nz,_ceda_cls_loop
+
+    pop     hl
+    pop     de
+    pop     bc
+    pop     af
+
+    ret
diff --git a/src/ceda_print.c b/src/ceda_print_c.c
similarity index 100%
rename from src/ceda_print.c
rename to src/ceda_print_c.c
diff --git a/src/main.c b/src/main.c
index 1675533..66c64de 100644
--- a/src/main.c
+++ b/src/main.c
@@ -4,6 +4,7 @@ int globalvar = 0x7777;
 
 int main(void) {
     ceda_print("Hello world!");
+    ceda_cls();
 
     return 0;
 }