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authorNao Pross <naopross@thearcway.org>2018-10-30 11:41:24 +0100
committerNao Pross <naopross@thearcway.org>2018-10-30 11:41:24 +0100
commit43be150dc6e84f6f6eeb071cd3cdb7fc21125d60 (patch)
tree541fd3d690c1bdfd7b68d684029a400b80f4aa06 /sw-old/z80/drivers/include/usart.h
parentAdd datasheets for ATmega328 and 74LS259 (diff)
downloadz80uPC-43be150dc6e84f6f6eeb071cd3cdb7fc21125d60.tar.gz
z80uPC-43be150dc6e84f6f6eeb071cd3cdb7fc21125d60.zip
Move sw to sw-old and hw to hw-altium, add kicad files
Diffstat (limited to 'sw-old/z80/drivers/include/usart.h')
-rw-r--r--sw-old/z80/drivers/include/usart.h158
1 files changed, 158 insertions, 0 deletions
diff --git a/sw-old/z80/drivers/include/usart.h b/sw-old/z80/drivers/include/usart.h
new file mode 100644
index 0000000..05aeb4a
--- /dev/null
+++ b/sw-old/z80/drivers/include/usart.h
@@ -0,0 +1,158 @@
+#ifndef __USART_H__
+#define __USART_H__
+
+#include "addresses.h"
+
+#include <stdint.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
+
+typedef unsigned int uint;
+typedef volatile uint8_t register_t;
+
+/* stuctures for usart registers */
+struct IER
+{
+ volatile uint received_data_interrupt :1;
+ volatile uint transmitter_empty_interrupt :1;
+ volatile uint receiver_line_status_interrupt :1;
+ volatile uint modem_status_interrupt :1;
+ volatile uint reserved :4;
+};
+
+struct IIR
+{
+ volatile uint interrupt_pending :1;
+ volatile uint interrupt_id :3;
+ volatile uint reserved :2;
+ volatile uint fifos :2;
+};
+
+struct FCR
+{
+ volatile uint fifo_enable :1;
+ volatile uint receiver_fifo_rst :1;
+ volatile uint trasmitter_fifo_rst :1;
+ volatile uint dma_mode_select :1;
+ volatile uint reserved :1;
+ volatile uint receiver_trigger :2;
+};
+
+struct LCR
+{
+ volatile uint word_length :2;
+ volatile uint stop_bits :1;
+ volatile uint parity :1;
+ volatile uint even_parity :1;
+ volatile uint stick_parity :1;
+ volatile uint break_control :1;
+ volatile uint divisor_latch_access :1;
+};
+
+struct MCR
+{
+ volatile uint data_terminal_ready :1;
+ volatile uint request_to_send :1;
+ volatile uint out1;
+ volatile uint out2;
+ volatile uint loop;
+ volatile uint autoflow :1;
+ volatile uint reserved :2;
+};
+
+struct LSR
+{
+ volatile uint data_ready :1;
+ volatile uint overrun_error :1;
+ volatile uint parity_error :1;
+ volatile uint framing_error :1;
+ volatile uint break_interrupt :1;
+ volatile uint transmitter_holder_empty :1;
+ volatile uint transmitter_empty :1;
+ volatile uint fifo_recv_error :1;
+};
+
+struct MSR
+{
+ volatile uint delta_cts :1;
+ volatile uint delta_data_set_ready :1;
+ volatile uint trailing_edge_ring_indicator :1;
+ volatile uint delta_data_carrier_detect :1;
+ volatile uint clear_to_send :1;
+ volatile uint data_set_ready :1;
+ volatile uint ring_indicator :1;
+ volatile uint data_carrier_detect :1;
+};
+
+/* this structure is only for internal use */
+struct _usart_device
+{
+ register_t buffer; // also used as LSB for divisor latch
+ struct IER IER;
+ struct IIR IIR;
+ struct FCR FCR;
+ struct LCR LCR;
+ struct MCR MCR;
+ struct LSR LSR;
+ struct MSR MSR;
+ register_t scratch;
+};
+
+
+// setup functions (wrappers)
+void usart_set_baudrate(uint16_t baudrate);
+void usart_set_parity(int mode);
+void usart_set_stop_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__