diff options
Diffstat (limited to 'src/emu/machine/74153.h')
-rw-r--r-- | src/emu/machine/74153.h | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/src/emu/machine/74153.h b/src/emu/machine/74153.h new file mode 100644 index 00000000000..2e7d9bdb487 --- /dev/null +++ b/src/emu/machine/74153.h @@ -0,0 +1,58 @@ +/***************************************************************************** + + 74153 Dual 4-line to 1-line data selectors/multiplexers + + + Pin layout and functions to access pins: + + enable_w(0) [1] /1G VCC [16] + b_w [2] B /2G [15] enable_w(1) + input_line_w(0,3) [3] 1C3 A [14] a_w + input_line_w(0,2) [4] 1C2 2C3 [13] input_line_w(1,3) + input_line_w(0,1) [5] 1C1 2C2 [12] input_line_w(1,2) + input_line_w(0,0) [6] 1C0 2C1 [11] input_line_w(1,1) + output_r(0) [7] 1Y 2C0 [10] input_line_w(1,0) + [8] GND 2Y [9] output_r(1) + + + Truth table (all logic levels indicate the actual voltage on the line): + + INPUTS | OUTPUT + | + G | B A | C0 C1 C2 C3 | Y + --+------+-------------+--- + H | X X | X X X X | L + L | L L | X X X X | C0 + L | L H | X X X X | C1 + L | H L | X X X X | C2 + L | H H | X X X X | C3 + --+------+-------------+--- + L = lo (0) + H = hi (1) + X = any state + +*****************************************************************************/ + +#ifndef TTL74153_H +#define TTL74153_H + + +/* The interface structure */ +struct TTL74153_interface +{ + void (*output_cb)(void); +}; + + +void TTL74153_config(int which, const struct TTL74153_interface *intf); + +/* must call TTL74153_update() after setting the inputs */ +void TTL74153_update(int which); + +void TTL74153_a_w(int which, int data); +void TTL74153_b_w(int which, int data); +void TTL74153_input_line_w(int which, int section, int input_line, int data); +void TTL74153_enable_w(int which, int section, int data); +int TTL74153_output_r(int which, int section); + +#endif |