diff options
author | 2011-09-02 14:53:41 +0000 | |
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committer | 2011-09-02 14:53:41 +0000 | |
commit | b764156f07218d6ae9701d0ac771b5f96304b482 (patch) | |
tree | d5a48461e71bb334af0b3e93406afff0b8d04f25 /src/emu/diserial.h | |
parent | ac2ff71b0cb85063fd0c9f0c4ede4178cc3691ee (diff) |
- Created device_serial_interface that should be used by UART's (no whatsnew)
- It is used by MESS side i8251 and 6551 are using it now
- Also created simple serial source devices (used by some cassette interface)
This will be optimized and rechecked after new chips are converted to use it
No whatsnew for now, but there will be info for the release.
Diffstat (limited to 'src/emu/diserial.h')
-rw-r--r-- | src/emu/diserial.h | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/src/emu/diserial.h b/src/emu/diserial.h new file mode 100644 index 00000000000..fa8b6fc932d --- /dev/null +++ b/src/emu/diserial.h @@ -0,0 +1,174 @@ +#pragma once + +#ifndef __EMU_H__ +#error Dont include this file directly; include emu.h instead. +#endif + +#ifndef __DISERIAL_H__ +#define __DISERIAL_H__ + +//************************************************************************** +// TYPE DEFINITIONS +//************************************************************************** +/* parity selections */ +/* if all the bits are added in a byte, if the result is: + even -> parity is even + odd -> parity is odd +*/ +enum +{ + SERIAL_PARITY_NONE, /* no parity. a parity bit will not be in the transmitted/received data */ + SERIAL_PARITY_ODD, /* odd parity */ + SERIAL_PARITY_EVEN /* even parity */ +}; + +/* + CTS = Clear to Send. (INPUT) + Other end of connection is ready to accept data + + + NOTE: + + This output is active low on serial chips (e.g. 0 is CTS is set), + but here it is active high! +*/ +#define SERIAL_STATE_CTS 0x0001 + +/* + RTS = Request to Send. (OUTPUT) + This end is ready to send data, and requests if the other + end is ready to accept it + + NOTE: + + This output is active low on serial chips (e.g. 0 is RTS is set), + but here it is active high! +*/ +#define SERIAL_STATE_RTS 0x0002 + +/* + DSR = Data Set ready. (INPUT) + Other end of connection has data + + + NOTE: + + This output is active low on serial chips (e.g. 0 is DSR is set), + but here it is active high! +*/ +#define SERIAL_STATE_DSR 0x0004 + +/* + DTR = Data terminal Ready. (OUTPUT) + TX contains new data. + + NOTE: + + This output is active low on serial chips (e.g. 0 is DTR is set), + but here it is active high! +*/ +#define SERIAL_STATE_DTR 0x0008 +/* RX = Recieve data. (INPUT) */ +#define SERIAL_STATE_RX_DATA 0x00010 +/* TX = Transmit data. (OUTPUT) */ +#define SERIAL_STATE_TX_DATA 0x00020 + + +// ======================> device_serial_interface +class device_serial_interface : public device_interface +{ +public: + // construction/destruction + device_serial_interface(const machine_config &mconfig, device_t &device); + virtual ~device_serial_interface(); + + virtual void input_callback(UINT8 state) = 0; + + void set_data_frame(int num_data_bits, int stop_bit_count, int parity_code); + + void receive_register_reset(); + void receive_register_update_bit(int bit); + void receive_register_extract(); + + + void transmit_register_reset(); + void transmit_register_add_bit(int bit); + void transmit_register_setup(UINT8 data_byte); + UINT8 transmit_register_get_data_bit(); + void transmit_register_send_bit(); + + UINT8 serial_helper_get_parity(UINT8 data) { return m_serial_parity_table[data]; } + + UINT8 get_in_data_bit() { return ((m_input_state & SERIAL_STATE_RX_DATA)>>4) & 1; } + void set_out_data_bit(UINT8 data) { m_connection_state &=~SERIAL_STATE_TX_DATA; m_connection_state |=(data<<5); } + + void serial_connection_out(); + + bool is_receive_register_full(); + bool is_transmit_register_empty(); + + UINT8 get_received_char() { return m_rcv_byte_received; } + + void set_callback(device_serial_interface *other_connection); + + void connect(device_serial_interface *other_connection); +protected: + UINT8 m_input_state; + UINT8 m_connection_state; +private: + UINT8 m_serial_parity_table[256]; + + // Data frame + // length of word in bits + UINT8 m_df_word_length; + // parity state + UINT8 m_df_parity; + // number of stop bits + UINT8 m_df_stop_bit_count; + + // Receive register + /* data */ + UINT16 m_rcv_register_data; + /* flags */ + UINT8 m_rcv_flags; + /* bit count received */ + UINT8 m_rcv_bit_count_received; + /* length of data to receive - includes data bits, parity bit and stop bit */ + UINT8 m_rcv_bit_count; + /* the byte of data received */ + UINT8 m_rcv_byte_received; + + // Transmit register + /* data */ + UINT16 m_tra_register_data; + /* flags */ + UINT8 m_tra_flags; + /* number of bits transmitted */ + UINT8 m_tra_bit_count_transmitted; + /* length of data to send */ + UINT8 m_tra_bit_count; + + device_serial_interface *m_other_connection; +}; + + +class serial_source_device : public device_t, + public device_serial_interface +{ +public: + // construction/destruction + serial_source_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock); + + virtual void input_callback(UINT8 state); + void send_bit(UINT8 data); +protected: + // device-level overrides + virtual void device_start(); +}; + +extern const device_type SERIAL_SOURCE; + +#define MCFG_SERIAL_SOURCE_ADD(_tag) \ + MCFG_DEVICE_ADD((_tag), SERIAL_SOURCE, 0) + +#endif /* __DISERIAL_H__ */ |