From 1ec8f14f03322e3fe1f56f4abcbc85f5c2934dfc Mon Sep 17 00:00:00 2001
From: Nao Pross <naopross@thearcway.org>
Date: Tue, 2 May 2017 16:14:41 +0200
Subject: fix for sdcc makefile

fix for the old makefile, because it could't compile more than one source file.
new libc directory with mem.c to start implementing the standard  C library
(or at least the part we need).
---
 sw/z80/kernel/include/types.h | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'sw/z80/kernel')

diff --git a/sw/z80/kernel/include/types.h b/sw/z80/kernel/include/types.h
index adde214..c24b311 100644
--- a/sw/z80/kernel/include/types.h
+++ b/sw/z80/kernel/include/types.h
@@ -6,4 +6,6 @@
 #define int16_t     int
 #define uint16_t    unsigned int
 
+#define size_t      uint16_t
+
 #endif
-- 
cgit v1.2.1


From 8a461a14c3ceaf42f1483abe51cda47ac785bfc9 Mon Sep 17 00:00:00 2001
From: Nao Pross <naopross@thearcway.org>
Date: Tue, 2 May 2017 22:09:40 +0200
Subject: add serial device struct

other changes:
  - change from main() to kmain() in crt0.s and kernel.c
  - new file devices.h to define all address locations for devices
  - new data type
      - register_t as volatile uint8_t for registers in devices
      - size_t from libc
---
 sw/z80/kernel/include/devices.h | 13 +++++++
 sw/z80/kernel/include/serial.h  | 85 +++++++++++++++++++++++++++++++++++++++++
 sw/z80/kernel/include/types.h   |  2 +
 sw/z80/kernel/kernel.c          |  7 +---
 4 files changed, 102 insertions(+), 5 deletions(-)
 create mode 100644 sw/z80/kernel/include/devices.h
 create mode 100644 sw/z80/kernel/include/serial.h

(limited to 'sw/z80/kernel')

diff --git a/sw/z80/kernel/include/devices.h b/sw/z80/kernel/include/devices.h
new file mode 100644
index 0000000..ea29065
--- /dev/null
+++ b/sw/z80/kernel/include/devices.h
@@ -0,0 +1,13 @@
+#ifndef __DEVICES_H__
+#define __DEVICES_H__
+
+#define ADDR_DEV_ROM_L      0x0000
+#define ADDR_DEV_ROM_H      0x2000
+
+#define ADDR_DEV_USART   0x4000
+#define ADDR_DEV_CTC     
+#define ADDR_DEV_PIO
+
+#define ADDR_DEV_RAM        0x8000
+
+#endif
diff --git a/sw/z80/kernel/include/serial.h b/sw/z80/kernel/include/serial.h
new file mode 100644
index 0000000..03e2448
--- /dev/null
+++ b/sw/z80/kernel/include/serial.h
@@ -0,0 +1,85 @@
+#ifndef __SERIAL_H__
+#define __SERIAL_H__
+
+#include "types.h"
+#include "devices.h"
+
+/* this structure is only for internal usage */
+struct _usart_device
+{
+    register_t buffer;  // also used as LSB for divisor latch
+
+    struct IER 
+    {
+        volatile int received_data_interrupt :1;
+        volatile int transmitter_empty_interrupt :1;
+        volatile int receiver_line_status_interrupt :1;
+        volatile int modem_status_interrupt :1;
+            volatile int reserved :4;
+    } IER;
+
+    struct IIR
+    {
+        volatile int interrupt_pending :1;
+        volatile int interrupt_id :3;
+        volatile int reserved :2;
+        volatile int fifos :2;
+    } IIR;
+
+    struct FCR
+    {
+        volatile int fifo_enable :1;
+        volatile int receiver_fifo_rst :1;
+    }
+
+    struct LCR
+    {
+        volatile int word_length :2;
+        volatile int stop_bits :1;
+        volatile int parity :1;
+        volatile int even_parity :1;
+        volatile int stick_parity :1;
+        volatile int break_control :1;
+        volatile int divisor_latch_access :1;
+    } LCR;
+
+    struct MCR
+    {
+        volatile int data_terminal_ready :1;
+        volatile int request_to_send :1;
+        volatile int out1;
+        volatile int out2;
+        volatile int loop;
+        volatile int autoflow :1;
+        volatile int reserved :2;
+    } MCR;
+
+    struct LSR 
+    {
+        volatile int data_ready :1;
+        volatile int overrun_error :1;
+        volatile int parity_error :1;
+        volatile int framing_error :1;
+        volatile int break_interrupt :1;
+        volatile int transmitter_register :1;
+        volatile int transmitter_emtpy :1;
+        volatile int fifo_recv_error :1;
+    } LSR;
+
+    struct MSR
+    {
+        volatile int delta_cts :1;
+        volatile int delta_data_set_ready :1;
+        volatile int trailing_edge_ring_indicator :1;
+        volatile int delta_data_carrier_detect :1;
+        volatile int clear_to_send :1;
+        volatile int data_set_ready :1;
+        volatile int ring_indicator :1;
+        volatile int data_carrier_detect :1;
+    } MSR;
+
+    register_t scratch;
+} *_usart = (_usart_device *) ADDR_DEV_USART;
+
+
+#endif // __SERIAL__H__
diff --git a/sw/z80/kernel/include/types.h b/sw/z80/kernel/include/types.h
index c24b311..552b7e9 100644
--- a/sw/z80/kernel/include/types.h
+++ b/sw/z80/kernel/include/types.h
@@ -1,6 +1,8 @@
 #ifndef __TYPES_H__
 #define __TYPES_H__
 
+#define register_t  volatile unsigned char
+
 #define int8_t      char
 #define uint8_t     unsigned char
 #define int16_t     int
diff --git a/sw/z80/kernel/kernel.c b/sw/z80/kernel/kernel.c
index fe87c3d..3db6579 100644
--- a/sw/z80/kernel/kernel.c
+++ b/sw/z80/kernel/kernel.c
@@ -1,10 +1,7 @@
 #include "types.h"
 
 
-void main(void)
+void kmain(void)
 {
-    int i, j = 20;
-    for (i = 0; i < 10; i++) {
-        j--;
-    }
+    
 }
-- 
cgit v1.2.1


From 4a7f45ee28ac0799ba1ca93fd1683f7858efc54a Mon Sep 17 00:00:00 2001
From: Nao Pross <naopross@thearcway.org>
Date: Fri, 2 Jun 2017 16:22:26 +0200
Subject: add serial interface and a few std library functions

changes in usart:
  - new functions to setup the serial comunication settings such as baudrate,
    parity and stop bits
  - init function with most common values
  - transmit and receive functions each with a wrapper to send data blocks

changes in libc:
  - new file stdio.c with basic implementation of putch, printf still a prototype
  - new file string.c with memcpy() function
---
 sw/z80/kernel/include/devices.h |   6 +-
 sw/z80/kernel/include/pio.h     |  18 +++++
 sw/z80/kernel/include/serial.h  |  85 -----------------------
 sw/z80/kernel/include/usart.h   | 149 ++++++++++++++++++++++++++++++++++++++++
 sw/z80/kernel/kernel.c          |   4 +-
 sw/z80/kernel/pio.c             |  29 ++++++++
 sw/z80/kernel/usart.c           |  91 ++++++++++++++++++++++++
 7 files changed, 292 insertions(+), 90 deletions(-)
 create mode 100644 sw/z80/kernel/include/pio.h
 delete mode 100644 sw/z80/kernel/include/serial.h
 create mode 100644 sw/z80/kernel/include/usart.h
 create mode 100644 sw/z80/kernel/pio.c
 create mode 100644 sw/z80/kernel/usart.c

(limited to 'sw/z80/kernel')

diff --git a/sw/z80/kernel/include/devices.h b/sw/z80/kernel/include/devices.h
index ea29065..e8c183f 100644
--- a/sw/z80/kernel/include/devices.h
+++ b/sw/z80/kernel/include/devices.h
@@ -4,9 +4,9 @@
 #define ADDR_DEV_ROM_L      0x0000
 #define ADDR_DEV_ROM_H      0x2000
 
-#define ADDR_DEV_USART   0x4000
-#define ADDR_DEV_CTC     
-#define ADDR_DEV_PIO
+#define ADDR_DEV_USART      0x4000
+#define ADDR_DEV_CTC        0x4100
+#define ADDR_DEV_PIO        0x4200
 
 #define ADDR_DEV_RAM        0x8000
 
diff --git a/sw/z80/kernel/include/pio.h b/sw/z80/kernel/include/pio.h
new file mode 100644
index 0000000..8d72ab0
--- /dev/null
+++ b/sw/z80/kernel/include/pio.h
@@ -0,0 +1,18 @@
+#ifndef __PIO_H__
+#define __PIO_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);
+
+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);
+
+// TODO: implement mode (in/out/both) and interrupt vector
+
+#endif // __PIO_H__
diff --git a/sw/z80/kernel/include/serial.h b/sw/z80/kernel/include/serial.h
deleted file mode 100644
index 03e2448..0000000
--- a/sw/z80/kernel/include/serial.h
+++ /dev/null
@@ -1,85 +0,0 @@
-#ifndef __SERIAL_H__
-#define __SERIAL_H__
-
-#include "types.h"
-#include "devices.h"
-
-/* this structure is only for internal usage */
-struct _usart_device
-{
-    register_t buffer;  // also used as LSB for divisor latch
-
-    struct IER 
-    {
-        volatile int received_data_interrupt :1;
-        volatile int transmitter_empty_interrupt :1;
-        volatile int receiver_line_status_interrupt :1;
-        volatile int modem_status_interrupt :1;
-            volatile int reserved :4;
-    } IER;
-
-    struct IIR
-    {
-        volatile int interrupt_pending :1;
-        volatile int interrupt_id :3;
-        volatile int reserved :2;
-        volatile int fifos :2;
-    } IIR;
-
-    struct FCR
-    {
-        volatile int fifo_enable :1;
-        volatile int receiver_fifo_rst :1;
-    }
-
-    struct LCR
-    {
-        volatile int word_length :2;
-        volatile int stop_bits :1;
-        volatile int parity :1;
-        volatile int even_parity :1;
-        volatile int stick_parity :1;
-        volatile int break_control :1;
-        volatile int divisor_latch_access :1;
-    } LCR;
-
-    struct MCR
-    {
-        volatile int data_terminal_ready :1;
-        volatile int request_to_send :1;
-        volatile int out1;
-        volatile int out2;
-        volatile int loop;
-        volatile int autoflow :1;
-        volatile int reserved :2;
-    } MCR;
-
-    struct LSR 
-    {
-        volatile int data_ready :1;
-        volatile int overrun_error :1;
-        volatile int parity_error :1;
-        volatile int framing_error :1;
-        volatile int break_interrupt :1;
-        volatile int transmitter_register :1;
-        volatile int transmitter_emtpy :1;
-        volatile int fifo_recv_error :1;
-    } LSR;
-
-    struct MSR
-    {
-        volatile int delta_cts :1;
-        volatile int delta_data_set_ready :1;
-        volatile int trailing_edge_ring_indicator :1;
-        volatile int delta_data_carrier_detect :1;
-        volatile int clear_to_send :1;
-        volatile int data_set_ready :1;
-        volatile int ring_indicator :1;
-        volatile int data_carrier_detect :1;
-    } MSR;
-
-    register_t scratch;
-} *_usart = (_usart_device *) ADDR_DEV_USART;
-
-
-#endif // __SERIAL__H__
diff --git a/sw/z80/kernel/include/usart.h b/sw/z80/kernel/include/usart.h
new file mode 100644
index 0000000..f1f428e
--- /dev/null
+++ b/sw/z80/kernel/include/usart.h
@@ -0,0 +1,149 @@
+#ifndef __USART_H__
+#define __USART_H__
+
+#include "types.h"
+#include "devices.h"
+
+#include "string.h"
+
+// baudrate clock divisors 
+// values from TL16C550C datasheet (table 9 for 1.8432 MHz crystal)
+#define USART_BAUDRATE_50       2304
+#define USART_BAUDRATE_75       1536
+#define USART_BAUDRATE_110      1047
+#define USART_BAUDRATE_134_5    857
+#define USART_BAUDRATE_150      768
+#define USART_BAUDRATE_300      384
+#define USART_BAUDRATE_600      192
+#define USART_BAUDRATE_1200     96
+#define USART_BAUDRATE_1800     64
+#define USART_BAUDRATE_2000     58
+#define USART_BAUDRATE_2400     48
+#define USART_BAUDRATE_3600     32
+#define USART_BAUDRATE_4800     24
+#define USART_BAUDRATE_7200     16
+#define USART_BAUDRATE_9600     12
+#define USART_BAUDRATE_19200    6
+#define USART_BAUDRATE_38400    3
+#define USART_BAUDRATE_56000    3
+
+// parity
+#define USART_PARITY_NONE       0
+#define USART_PARITY_EVEN       1
+#define USART_PARITY_ODD        2
+
+// stop bits
+#define USART_STOP_BITS_1       10
+#define USART_STOP_BITS_15      15
+#define USART_STOP_BITS_2       20
+
+// word lenght
+#define USART_WORD_LENGTH_5     0
+#define USART_WORD_LENGTH_6     1
+#define USART_WORD_LENGTH_7     2
+#define USART_WORD_LENGTH_8     3
+
+// autoflow
+#define USART_AUTOFLOW_ALL      3
+#define USART_AUTOFLOW_CTS      2
+#define USART_AUTOFLOW_OFF      0
+
+
+/* this structure is only for internal usage */
+struct _usart_device
+{
+    register_t buffer;  // also used as LSB for divisor latch
+
+    struct IER 
+    {
+        volatile int received_data_interrupt :1;
+        volatile int transmitter_empty_interrupt :1;
+        volatile int receiver_line_status_interrupt :1;
+        volatile int modem_status_interrupt :1;
+        volatile int reserved :4;
+    } IER;
+
+    struct IIR
+    {
+        volatile int interrupt_pending :1;
+        volatile int interrupt_id :3;
+        volatile int reserved :2;
+        volatile int fifos :2;
+    } IIR;
+
+    struct FCR
+    {
+        volatile int fifo_enable :1;
+        volatile int receiver_fifo_rst :1;
+        volatile int trasmitter_fifo_rst :1;
+        volatile int dma_mode_select :1;
+        volatile int reserved :1;
+        volatile int receiver_trigger :2;
+    } FCR;
+
+    struct LCR
+    {
+        volatile int word_length :2;
+        volatile int stop_bits :1;
+        volatile int parity :1;
+        volatile int even_parity :1;
+        volatile int stick_parity :1;
+        volatile int break_control :1;
+        volatile int divisor_latch_access :1;
+    } LCR;
+
+    struct MCR
+    {
+        volatile int data_terminal_ready :1;
+        volatile int request_to_send :1;
+        volatile int out1;
+        volatile int out2;
+        volatile int loop;
+        volatile int autoflow :1;
+        volatile int reserved :2;
+    } MCR;
+
+    struct LSR 
+    {
+        volatile int data_ready :1;
+        volatile int overrun_error :1;
+        volatile int parity_error :1;
+        volatile int framing_error :1;
+        volatile int break_interrupt :1;
+        volatile int transmitter_holder_empty :1;
+        volatile int transmitter_empty :1;
+        volatile int fifo_recv_error :1;
+    } LSR;
+
+    struct MSR
+    {
+        volatile int delta_cts :1;
+        volatile int delta_data_set_ready :1;
+        volatile int trailing_edge_ring_indicator :1;
+        volatile int delta_data_carrier_detect :1;
+        volatile int clear_to_send :1;
+        volatile int data_set_ready :1;
+        volatile int ring_indicator :1;
+        volatile int data_carrier_detect :1;
+    } MSR;
+
+    register_t scratch;
+};
+
+
+// setup functions (wrappers)
+void usart_set_baudrate(uint16_t baudrate);
+void usart_set_parity(int mode);
+void usart_set_stob_bits(int count);
+void usart_set_word_length(int length);
+void usart_set_autoflow(int mode);
+
+inline void usart_init(uint16_t baudrate, int parity, int stop_bits); 
+
+void usart_transmit(uint8_t data);
+uint8_t usart_receive();
+
+int usart_write(uint8_t *data, size_t size);
+int usart_read(uint8_t *buffer, size_t count);
+
+#endif // __USART__H__
diff --git a/sw/z80/kernel/kernel.c b/sw/z80/kernel/kernel.c
index 3db6579..3d5aeb6 100644
--- a/sw/z80/kernel/kernel.c
+++ b/sw/z80/kernel/kernel.c
@@ -1,7 +1,7 @@
 #include "types.h"
-
+#include "usart.h"
 
 void kmain(void)
 {
-    
+    usart_init(USART_BAUDRATE_9600, USART_PARITY_EVEN, USART_STOP_BITS_1);
 }
diff --git a/sw/z80/kernel/pio.c b/sw/z80/kernel/pio.c
new file mode 100644
index 0000000..e8c7e24
--- /dev/null
+++ b/sw/z80/kernel/pio.c
@@ -0,0 +1,29 @@
+#include "pio.h"
+
+static uint8_t *pio_port_a = (uint8_t *) ADDR_DEV_PIO;
+static uint8_t *pio_port_b = (uint8_t *) ADDR_DEV_PIO + 1;
+static uint8_t *pio_ctrl_a = (uint8_t *) ADDR_DEV_PIO + 2;
+static uint8_t *pio_ctrl_b = (uint8_t *) ADDR_DEV_PIO + 3;
+
+void pio_data(int port, uint8_t data)
+{
+    if (port == PIO_A)
+        *pio_port_a = cmd;
+    else
+        *pio_port_b = cmd;
+}
+
+void pio_command(int port, uint8_t cmd)
+{
+    if (port == PIO_A)
+        *pio_ctrl_a = cmd;
+    else
+        *pio_ctrl_b = cmd;
+}
+
+
+
+inline int pio_read_pin(int port, uint8_t pin)
+{
+
+}
diff --git a/sw/z80/kernel/usart.c b/sw/z80/kernel/usart.c
new file mode 100644
index 0000000..4c2fdaf
--- /dev/null
+++ b/sw/z80/kernel/usart.c
@@ -0,0 +1,91 @@
+#include "usart.h"
+
+static struct _usart_device *_usart = (struct _usart_device *) ADDR_DEV_USART;
+
+void usart_set_baudrate(uint16_t baudrate)
+{
+    // enable latch access
+    _usart->LCR.divisor_latch_access = 1;
+    _usart->buffer = 0x00FF & baudrate; // LSBs
+    memcpy(&_usart->IER, &(baudrate >>8), 1);
+    // _usart->IER    = 0x00FF & (baudrate >> 8); // MSBs
+    _usart->LCR.divisor_latch_access = 0;
+}
+
+void usart_set_parity(int mode)
+{
+    if (mode == USART_PARITY_EVEN) {
+        _usart->LCR.even_parity = 1;
+    }
+    else if (mode == USART_PARITY_ODD) {
+        _usart->LCR.even_parity = 0;
+    }
+
+     _usart->LCR.parity = (mode == USART_PARITY_NONE) ? 0 : 1;
+}
+
+void usart_set_stop_bits(int count)
+{
+    _usart->LCR.stop_bits = (count == USART_STOP_BITS_1) ? 0 : 1;
+}
+
+void usart_word_length(int length)
+{
+    _usart->LCR.word_length = length;
+}
+
+void usart_set_autoflow(int mode)
+{
+    _usart->MCR.autoflow = (mode == USART_AUTOFLOW_OFF) ? 0 : 1;
+    _usart->MCR.data_terminal_ready = (mode == USART_AUTOFLOW_ALL);
+}
+
+inline void usart_init(uint16_t baudrate, int parity, int stop_bits)
+{
+    usart_set_baudrate(baudrate);
+    usart_set_parity(parity);
+    usart_set_stop_bits(stop_bits);
+    usart_set_autoflow(USART_AUTOFLOW_OFF);
+}
+
+void usart_transmit(uint8_t data)
+{
+    _usart->buffer = data;
+    while (_usart->LSR.transmitter_holder_empty == 0); // wait
+}
+
+uint8_t usart_receive()
+{
+    return _usart->buffer;
+}
+
+int usart_write(uint8_t *data, size_t size)
+{
+    uint8_t *dp = data;
+
+    while (size--) {
+        _usart->buffer = *(dp++);
+    }
+    while (_usart->LSR.transmitter_empty);
+
+    // TODO: do something that actually counts for sent bytes 
+    return size;
+}
+
+int usart_read(uint8_t *buffer, size_t count)
+{
+    uint8_t *bp = buffer;
+    size_t read_count = 0;
+
+    while (count--) {
+        *(bp++) = _usart->buffer;
+        // check for errors
+        if (_usart->LSR.framing_error || _usart->LSR.parity_error) {
+            bp--; // delete last byte (?)
+        } else {
+           read_count++;
+        }
+    }
+
+    return read_count;
+}
-- 
cgit v1.2.1


From b96b0d6c00ea72895582ec14f9c7dccd3fe7062a Mon Sep 17 00:00:00 2001
From: Nao Pross <naopross@thearcway.org>
Date: Sat, 10 Jun 2017 17:47:36 +0200
Subject: 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.
---
 sw/z80/kernel/include/pio.h | 27 ++++++++++++++++++++++-----
 sw/z80/kernel/pio.c         | 25 +++++++------------------
 sw/z80/kernel/usart.c       |  4 ++--
 3 files changed, 31 insertions(+), 25 deletions(-)

(limited to 'sw/z80/kernel')

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);
diff --git a/sw/z80/kernel/pio.c b/sw/z80/kernel/pio.c
index e8c7e24..4b9caee 100644
--- a/sw/z80/kernel/pio.c
+++ b/sw/z80/kernel/pio.c
@@ -1,29 +1,18 @@
 #include "pio.h"
 
-static uint8_t *pio_port_a = (uint8_t *) ADDR_DEV_PIO;
-static uint8_t *pio_port_b = (uint8_t *) ADDR_DEV_PIO + 1;
-static uint8_t *pio_ctrl_a = (uint8_t *) ADDR_DEV_PIO + 2;
-static uint8_t *pio_ctrl_b = (uint8_t *) ADDR_DEV_PIO + 3;
+static uint8_t *pio_port = (uint8_t *) ADDR_DEV_PIO;
+static uint8_t *pio_ctrl = (uint8_t *) (ADDR_DEV_PIO + 2);
 
-void pio_data(int port, uint8_t data)
+void _pio_data(int port, uint8_t data)
 {
-    if (port == PIO_A)
-        *pio_port_a = cmd;
-    else
-        *pio_port_b = cmd;
+    *(pio_port + port) = data;
 }
 
-void pio_command(int port, uint8_t cmd)
+void _pio_command(int port, uint8_t cmd)
 {
-    if (port == PIO_A)
-        *pio_ctrl_a = cmd;
-    else
-        *pio_ctrl_b = cmd;
+    *(pio_ctrl + port) = cmd;
 }
 
-
-
-inline int pio_read_pin(int port, uint8_t pin)
+void pio_set_mode(int port, int mode)
 {
-
 }
diff --git a/sw/z80/kernel/usart.c b/sw/z80/kernel/usart.c
index 4c2fdaf..9ec6dbd 100644
--- a/sw/z80/kernel/usart.c
+++ b/sw/z80/kernel/usart.c
@@ -65,8 +65,8 @@ int usart_write(uint8_t *data, size_t size)
 
     while (size--) {
         _usart->buffer = *(dp++);
+        while (_usart->LSR.transmitter_empty);
     }
-    while (_usart->LSR.transmitter_empty);
 
     // TODO: do something that actually counts for sent bytes 
     return size;
@@ -83,7 +83,7 @@ int usart_read(uint8_t *buffer, size_t count)
         if (_usart->LSR.framing_error || _usart->LSR.parity_error) {
             bp--; // delete last byte (?)
         } else {
-           read_count++;
+            read_count++;
         }
     }
 
-- 
cgit v1.2.1


From 436e259b4c3d687bab51cc8ca35fe61103b430a2 Mon Sep 17 00:00:00 2001
From: Nao Pross <naopross@thearcway.org>
Date: Fri, 16 Jun 2017 13:51:06 +0200
Subject: fixed typo in usart.h and in doc

---
 sw/z80/kernel/include/usart.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'sw/z80/kernel')

diff --git a/sw/z80/kernel/include/usart.h b/sw/z80/kernel/include/usart.h
index f1f428e..3e5c070 100644
--- a/sw/z80/kernel/include/usart.h
+++ b/sw/z80/kernel/include/usart.h
@@ -134,7 +134,7 @@ struct _usart_device
 // setup functions (wrappers)
 void usart_set_baudrate(uint16_t baudrate);
 void usart_set_parity(int mode);
-void usart_set_stob_bits(int count);
+void usart_set_stop_bits(int count);
 void usart_set_word_length(int length);
 void usart_set_autoflow(int mode);
 
-- 
cgit v1.2.1