IGS Mahjong lhb dbc lhbv33c ryukobou have no coin1 input (the drive is igs011.cpp)

[little0000bag]

MAME version

0.270

System information

Windows 11, 64 -bit, version 21H2, Chinese, Chinese
X86-64, 24GB System Ram

INI configuration details

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Emulated system/software

No response

Incorrect behaviour

IGS Mahjong lhb dbc lhbv33c ryukobou have no coin1 input (the drive is igs011.cpp).
when I remove the coin1 input , and remove the code of "PORT_IMPULSE(5)" , the coin1 input key "5" works.
PORT_START("COIN")
PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_CUSTOM ) PORT_READ_LINE_MEMBER(FUNC(igs011_state::igs_hopper_r)) // hopper switch
PORT_BIT( 0x02, IP_ACTIVE_LOW, IPT_SERVICE2 ) // system reset
PORT_SERVICE_NO_TOGGLE( 0x04, IP_ACTIVE_LOW ) // keep pressed while booting
PORT_BIT( 0x08, IP_ACTIVE_LOW, IPT_SERVICE1 ) // stats
PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_COIN1 ) PORT_IMPULSE(5)
PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_OTHER ) PORT_NAME("Pay Out") PORT_CODE(KEYCODE_O) // clear coins
PORT_BIT( 0x40, IP_ACTIVE_LOW, IPT_OTHER ) PORT_NAME("0") PORT_CODE(KEYCODE_0_PAD) // shown in test mode
PORT_BIT( 0x80, IP_ACTIVE_LOW, IPT_UNKNOWN )

Expected behaviour

PORT_START("COIN")
PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_CUSTOM ) PORT_READ_LINE_MEMBER(FUNC(igs011_state::igs_hopper_r)) // hopper switch
PORT_BIT( 0x02, IP_ACTIVE_LOW, IPT_SERVICE2 )   // system reset
PORT_SERVICE_NO_TOGGLE( 0x04, IP_ACTIVE_LOW )   // keep pressed while booting
PORT_BIT( 0x08, IP_ACTIVE_LOW, IPT_SERVICE1 )   // stats
**_PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_COIN1    )_** 
PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_OTHER    ) PORT_NAME("Pay Out") PORT_CODE(KEYCODE_O) // clear coins
PORT_BIT( 0x40, IP_ACTIVE_LOW, IPT_OTHER    ) PORT_NAME("0") PORT_CODE(KEYCODE_0_PAD)   // shown in test mode
PORT_BIT( 0x80, IP_ACTIVE_LOW, IPT_UNKNOWN  )

Steps to reproduce

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Additional details

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