add port interface header, api still to implement

fix for bug in usart.c, in function usart_write() that checked the
trasmission_empty register at the wrong time causing it to overwrite
the buffer.

1 files changed, 22 insertions, 5 deletions

diff --git a/sw/z80/kernel/include/pio.h b/sw/z80/kernel/include/pio.h
index 8d72ab0..5d289ca 100644
--- a/sw/z80/kernel/include/pio.h
+++ b/sw/z80/kernel/include/pio.h
@@ -1,14 +1,31 @@
 #ifndef __PIO_H__
 #define __PIO_H__
 
-#define PIO_A   0
-#define PIO_B   1
+#include "devices.h"
+#include "types.h"
 
+#define PIO_A       0
+#define PIO_B       1
 
-void pio_data(int port, uint8_t data);
-void pio_command(int port, uint8_t cmd);
+#define PIO_MODE_0  0
+#define PIO_MODE_1  1
+#define PIO_MODE_2  2
+#define PIO_MODE_3  3
 
-uint8_t pio_read_data(int port);
+#define PIO_INT_ACTIVE_HIGH     (1<<5)
+#define PIO_INT_AND_MODE        (1<<6)
+#define PIO_INT_ENABLE          (1<<7)
+
+
+void _pio_data(int port, uint8_t data);
+void _pio_command(int port, uint8_t cmd);
+
+void pio_set_mode(int port, int mode);
+void pio_set_interrupts(int port, int control);
+void pio_set_interrupts_mask(int port, uint8_t mask);
+void pio_set_io(int port, uint8_t io);
+
+// uint8_t pio_read_data(int port);
 
 inline int pio_read_pin(int port, uint8_t pin);
 inline void pio_write_pin(int port, uint8_t pin);