2 Copyright 2014 Jun WAKO <wakojun@gmail.com>
7 #define IBM4704_ERR_NONE 0
8 #define IBM4704_ERR_PARITY 0x70
11 void ibm4704_init(void);
12 uint8_t ibm4704_send(uint8_t data);
13 uint8_t ibm4704_recv_response(void);
14 uint8_t ibm4704_recv(void);
17 /* Check pin configuration */
18 #if !(defined(IBM4704_CLOCK_PORT) && \
19 defined(IBM4704_CLOCK_PIN) && \
20 defined(IBM4704_CLOCK_DDR) && \
21 defined(IBM4704_CLOCK_BIT))
22 # error "ibm4704 clock pin configuration is required in config.h"
25 #if !(defined(IBM4704_DATA_PORT) && \
26 defined(IBM4704_DATA_PIN) && \
27 defined(IBM4704_DATA_DDR) && \
28 defined(IBM4704_DATA_BIT))
29 # error "ibm4704 data pin configuration is required in config.h"
33 /*--------------------------------------------------------------------
35 *------------------------------------------------------------------*/
36 static inline void clock_lo(void)
38 IBM4704_CLOCK_PORT &= ~(1<<IBM4704_CLOCK_BIT);
39 IBM4704_CLOCK_DDR |= (1<<IBM4704_CLOCK_BIT);
41 static inline void clock_hi(void)
43 /* input with pull up */
44 IBM4704_CLOCK_DDR &= ~(1<<IBM4704_CLOCK_BIT);
45 IBM4704_CLOCK_PORT |= (1<<IBM4704_CLOCK_BIT);
47 static inline bool clock_in(void)
49 IBM4704_CLOCK_DDR &= ~(1<<IBM4704_CLOCK_BIT);
50 IBM4704_CLOCK_PORT |= (1<<IBM4704_CLOCK_BIT);
52 return IBM4704_CLOCK_PIN&(1<<IBM4704_CLOCK_BIT);
54 static inline void data_lo(void)
56 IBM4704_DATA_PORT &= ~(1<<IBM4704_DATA_BIT);
57 IBM4704_DATA_DDR |= (1<<IBM4704_DATA_BIT);
59 static inline void data_hi(void)
61 /* input with pull up */
62 IBM4704_DATA_DDR &= ~(1<<IBM4704_DATA_BIT);
63 IBM4704_DATA_PORT |= (1<<IBM4704_DATA_BIT);
65 static inline bool data_in(void)
67 IBM4704_DATA_DDR &= ~(1<<IBM4704_DATA_BIT);
68 IBM4704_DATA_PORT |= (1<<IBM4704_DATA_BIT);
70 return IBM4704_DATA_PIN&(1<<IBM4704_DATA_BIT);
73 static inline uint16_t wait_clock_lo(uint16_t us)
75 while (clock_in() && us) { asm(""); _delay_us(1); us--; }
78 static inline uint16_t wait_clock_hi(uint16_t us)
80 while (!clock_in() && us) { asm(""); _delay_us(1); us--; }
83 static inline uint16_t wait_data_lo(uint16_t us)
85 while (data_in() && us) { asm(""); _delay_us(1); us--; }
88 static inline uint16_t wait_data_hi(uint16_t us)
90 while (!data_in() && us) { asm(""); _delay_us(1); us--; }
94 /* idle state that device can send */
95 static inline void idle(void)
101 /* inhibit device to send
102 * keyboard checks Data line on start bit(Data:hi) and it stops sending if Data line is low.
104 static inline void inhibit(void)