diff --git a/src/devices/machine/74259.cpp b/src/devices/machine/74259.cpp
index 021be2a1a34..fdd0354e622 100644
--- a/src/devices/machine/74259.cpp
+++ b/src/devices/machine/74259.cpp
@@ -313,23 +313,23 @@ WRITE8_MEMBER(addressable_latch_device::write_a3)
 }
 
 //-------------------------------------------------
-//  write_nibble - write handler using LSB of
+//  write_nibble_d0 - write handler using LSB of
 //  data as input and next three bits as address
 //  (offset is ignored)
 //-------------------------------------------------
 
-WRITE8_MEMBER(addressable_latch_device::write_nibble)
+WRITE8_MEMBER(addressable_latch_device::write_nibble_d0)
 {
 	write_bit((data & 0x0e) >> 1, data & 0x01);
 }
 
 //-------------------------------------------------
-//  write_nibble_alt - write handler using bit 3 of
+//  write_nibble_d3 - write handler using bit 3 of
 //  data as input and lowest three bits as address
 //  (offset is ignored)
 //-------------------------------------------------
 
-WRITE8_MEMBER(addressable_latch_device::write_nibble_alt)
+WRITE8_MEMBER(addressable_latch_device::write_nibble_d3)
 {
 	write_bit(data & 0x07, BIT(data, 3));
 }
diff --git a/src/devices/machine/74259.h b/src/devices/machine/74259.h
index 5cdb51e80f6..0805537d06b 100644
--- a/src/devices/machine/74259.h
+++ b/src/devices/machine/74259.h
@@ -77,8 +77,8 @@ public:
 	DECLARE_WRITE8_MEMBER(write_d7);
 	DECLARE_WRITE8_MEMBER(write_a0);
 	DECLARE_WRITE8_MEMBER(write_a3);
-	DECLARE_WRITE8_MEMBER(write_nibble);
-	DECLARE_WRITE8_MEMBER(write_nibble_alt);
+	DECLARE_WRITE8_MEMBER(write_nibble_d0);
+	DECLARE_WRITE8_MEMBER(write_nibble_d3);
 	DECLARE_WRITE8_MEMBER(clear);
 
 	// read handlers (inlined for the sake of optimization)
diff --git a/src/mame/drivers/bigbord2.cpp b/src/mame/drivers/bigbord2.cpp
index 5e5c39d958c..6a474cbc740 100644
--- a/src/mame/drivers/bigbord2.cpp
+++ b/src/mame/drivers/bigbord2.cpp
@@ -335,14 +335,14 @@ static ADDRESS_MAP_START( bigbord2_io, AS_IO, 8, bigbord2_state )
 	AM_RANGE(0x84, 0x87) AM_DEVREADWRITE("ctc1", z80ctc_device, read, write) // u37 has issues
 	AM_RANGE(0x88, 0x8b) AM_DEVREADWRITE("ctc2", z80ctc_device, read, write) // u21
 	AM_RANGE(0x8c, 0x8f) AM_DEVREADWRITE("dma", z80dma_device, read, write) // u62
-	AM_RANGE(0xc0, 0xc3) AM_DEVWRITE("proglatch", ls259_device, write_nibble_alt) // u41 - eprom programming port
+	AM_RANGE(0xc0, 0xc3) AM_DEVWRITE("proglatch", ls259_device, write_nibble_d3) // u41 - eprom programming port
 	AM_RANGE(0xc4, 0xc7) AM_READ(status_port_r) // u11
-	AM_RANGE(0xc8, 0xcb) AM_DEVWRITE("syslatch1", ls259_device, write_nibble_alt) // u14
+	AM_RANGE(0xc8, 0xcb) AM_DEVWRITE("syslatch1", ls259_device, write_nibble_d3) // u14
 	AM_RANGE(0xcc, 0xcf) AM_WRITE(syslatch2_w)
 	AM_RANGE(0xd0, 0xd3) AM_READ(kbd_r) // u1
 	AM_RANGE(0xd4, 0xd7) AM_DEVREADWRITE("fdc", mb8877_device, read, write) // u10
 	//AM_RANGE(0xd8, 0xdb) AM_READWRITE(portd8_r, portd8_w) // various external data ports; DB = centronics printer
-	AM_RANGE(0xd9, 0xd9) AM_DEVWRITE("outlatch1", ls259_device, write_nibble_alt) // u96
+	AM_RANGE(0xd9, 0xd9) AM_DEVWRITE("outlatch1", ls259_device, write_nibble_d3) // u96
 	AM_RANGE(0xdc, 0xdc) AM_MIRROR(2) AM_DEVREADWRITE("crtc", mc6845_device, status_r, address_w) // u30
 	AM_RANGE(0xdd, 0xdd) AM_MIRROR(2) AM_DEVREADWRITE("crtc", mc6845_device, register_r, register_w)
 ADDRESS_MAP_END
diff --git a/src/mame/drivers/mjsister.cpp b/src/mame/drivers/mjsister.cpp
index 8af28e02564..cbf83c77eec 100644
--- a/src/mame/drivers/mjsister.cpp
+++ b/src/mame/drivers/mjsister.cpp
@@ -327,8 +327,8 @@ static ADDRESS_MAP_START( mjsister_io_map, AS_IO, 8, mjsister_state )
 	AM_RANGE(0x12, 0x12) AM_DEVWRITE("aysnd", ay8910_device, data_w)
 	AM_RANGE(0x20, 0x20) AM_READ(keys_r)
 	AM_RANGE(0x21, 0x21) AM_READ_PORT("IN0")
-	AM_RANGE(0x30, 0x30) AM_DEVWRITE("mainlatch1", ls259_device, write_nibble)
-	AM_RANGE(0x31, 0x31) AM_DEVWRITE("mainlatch2", ls259_device, write_nibble)
+	AM_RANGE(0x30, 0x30) AM_DEVWRITE("mainlatch1", ls259_device, write_nibble_d0)
+	AM_RANGE(0x31, 0x31) AM_DEVWRITE("mainlatch2", ls259_device, write_nibble_d0)
 	AM_RANGE(0x32, 0x32) AM_WRITE(input_sel1_w)
 	AM_RANGE(0x33, 0x33) AM_WRITE(input_sel2_w)
 	AM_RANGE(0x34, 0x34) AM_WRITE(dac_adr_s_w)
diff --git a/src/mame/drivers/toaplan1.cpp b/src/mame/drivers/toaplan1.cpp
index c5e07316232..e41835300ef 100644
--- a/src/mame/drivers/toaplan1.cpp
+++ b/src/mame/drivers/toaplan1.cpp
@@ -843,7 +843,7 @@ static ADDRESS_MAP_START( rallybik_sound_io_map, AS_IO, 8, toaplan1_rallybik_sta
 	AM_RANGE(0x00, 0x00) AM_READ_PORT("P1")
 	AM_RANGE(0x10, 0x10) AM_READ_PORT("P2")
 	AM_RANGE(0x20, 0x20) AM_READ_PORT("SYSTEM")
-	AM_RANGE(0x30, 0x30) AM_DEVWRITE("coinlatch", ls259_device, write_nibble)  /* Coin counter/lockout */
+	AM_RANGE(0x30, 0x30) AM_DEVWRITE("coinlatch", ls259_device, write_nibble_d0)  /* Coin counter/lockout */
 	AM_RANGE(0x40, 0x40) AM_READ_PORT("DSWA")
 	AM_RANGE(0x50, 0x50) AM_READ_PORT("DSWB")
 	AM_RANGE(0x60, 0x61) AM_DEVREADWRITE("ymsnd", ym3812_device, read, write)