diff --git a/src/mame/drivers/at.cpp b/src/mame/drivers/at.cpp
index 012921227a5..e9e022dae05 100644
--- a/src/mame/drivers/at.cpp
+++ b/src/mame/drivers/at.cpp
@@ -1,4 +1,4 @@
-// license:BSD-3-Clausekbd
+// license:BSD-3-Clause
 // copyright-holders:Wilbert Pol, Miodrag Milanovic
 /***************************************************************************
 
@@ -516,8 +516,8 @@ void at_state::ibm5170(machine_config &config)
 	ISA16_SLOT(config, "isa4", 0, "mb:isabus", pc_isa16_cards, "ide", false);
 
 	pc_kbdc_device &pc_kbdc(PC_KBDC(config, "kbd", pc_at_keyboards, STR_KBD_IBM_PC_AT_84));
-	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_clk_w));
-	pc_kbdc.out_data_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_data_w));
+	pc_kbdc.out_clock_cb().set(m_mb, FUNC(at_mb_device::kbd_clk_w));
+	pc_kbdc.out_data_cb().set(m_mb, FUNC(at_mb_device::kbd_data_w));
 
 	/* internal ram */
 	RAM(config, m_ram).set_default_size("1664K").set_extra_options("640K,1024K,2M,4M,8M,15M");
@@ -632,8 +632,8 @@ void at_state::at386(machine_config &config)
 	ISA16_SLOT(config, "isa5", 0, "mb:isabus", pc_isa16_cards, nullptr, false);
 
 	pc_kbdc_device &pc_kbdc(PC_KBDC(config, "kbd", pc_at_keyboards, STR_KBD_MICROSOFT_NATURAL));
-	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_clk_w));
-	pc_kbdc.out_data_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_data_w));
+	pc_kbdc.out_clock_cb().set(m_mb, FUNC(at_mb_device::kbd_clk_w));
+	pc_kbdc.out_data_cb().set(m_mb, FUNC(at_mb_device::kbd_data_w));
 
 	/* internal ram */
 	RAM(config, m_ram).set_default_size("1664K").set_extra_options("2M,4M,8M,15M,16M,32M,64M");
@@ -673,8 +673,8 @@ void at_state::at486(machine_config &config)
 	ISA16_SLOT(config, "isa5", 0, "mb:isabus", pc_isa16_cards, nullptr, false);
 
 	pc_kbdc_device &pc_kbdc(PC_KBDC(config, "kbd", pc_at_keyboards, STR_KBD_MICROSOFT_NATURAL));
-	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_clk_w));
-	pc_kbdc.out_data_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_data_w));
+	pc_kbdc.out_clock_cb().set(m_mb, FUNC(at_mb_device::kbd_clk_w));
+	pc_kbdc.out_data_cb().set(m_mb, FUNC(at_mb_device::kbd_data_w));
 
 	/* internal ram */
 	RAM(config, m_ram).set_default_size("4M").set_extra_options("1M,2M,8M,16M,20M,32M,64M,128M");
@@ -783,8 +783,8 @@ void megapc_state::megapc(machine_config &config)
 	keybc.kbd_data().set("kbd", FUNC(pc_kbdc_device::data_write_from_mb));
 
 	pc_kbdc_device &pc_kbdc(PC_KBDC(config, "kbd", pc_at_keyboards, STR_KBD_MICROSOFT_NATURAL));
-	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_clk_w));
-	pc_kbdc.out_data_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_data_w));
+	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_mb_device::kbd_clk_w));
+	pc_kbdc.out_data_cb().set("keybc", FUNC(at_mb_device::kbd_data_w));
 
 	/* internal ram */
 	RAM(config, m_ram).set_default_size("4M").set_extra_options("1M,2M,8M,15M,16M");
@@ -837,8 +837,8 @@ void at_vrom_fix_state::megapcpla(machine_config &config)
 	ISA16_SLOT(config, "isa5", 0, "mb:isabus", pc_isa16_cards, nullptr, false);
 
 	pc_kbdc_device &pc_kbdc(PC_KBDC(config, "kbd", pc_at_keyboards, STR_KBD_MICROSOFT_NATURAL));
-	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_clk_w));
-	pc_kbdc.out_data_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_data_w));
+	pc_kbdc.out_clock_cb().set(m_mb, FUNC(at_mb_device::kbd_clk_w));
+	pc_kbdc.out_data_cb().set(m_mb, FUNC(at_mb_device::kbd_data_w));
 
 	/* internal ram */
 	RAM(config, m_ram).set_default_size("4M").set_extra_options("2M,8M,15M,16M,32M,64M,128M,256M");
@@ -884,8 +884,8 @@ void at_state::ficpio2(machine_config &config)
 	ISA16_SLOT(config, "isa4", 0, "mb:isabus", pc_isa16_cards, nullptr, false);
 
 	pc_kbdc_device &pc_kbdc(PC_KBDC(config, "kbd", pc_at_keyboards, STR_KBD_MICROSOFT_NATURAL));
-	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_clk_w));
-	pc_kbdc.out_data_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_data_w));
+	pc_kbdc.out_clock_cb().set(m_mb, FUNC(at_mb_device::kbd_clk_w));
+	pc_kbdc.out_data_cb().set(m_mb, FUNC(at_mb_device::kbd_data_w));
 
 	vt82c496_device &chipset(VT82C496(config, "chipset"));
 	chipset.set_cputag(m_maincpu);
@@ -918,8 +918,8 @@ void at_state::comportiii(machine_config &config)
 	ISA16_SLOT(config, "isa2",   0, "mb:isabus", pc_isa16_cards, nullptr, false);
 
 	pc_kbdc_device &pc_kbdc(PC_KBDC(config, "kbd", pc_at_keyboards, STR_KBD_IBM_PC_AT_84));
-	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_clk_w));
-	pc_kbdc.out_data_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_data_w));
+	pc_kbdc.out_clock_cb().set(m_mb, FUNC(at_mb_device::kbd_clk_w));
+	pc_kbdc.out_data_cb().set(m_mb, FUNC(at_mb_device::kbd_data_w));
 
 	/* internal ram */
 	RAM(config, m_ram).set_default_size("640K").set_extra_options("1152K,1664K,2176K,2688K,4736K,6784K");
@@ -1009,8 +1009,8 @@ void at_state::pg750(machine_config &config)
 	ISA16_SLOT(config, "isa5", 0, "mb:isabus", pc_isa16_cards, nullptr, false);
 
 	pc_kbdc_device &pc_kbdc(PC_KBDC(config, "kbd", pc_at_keyboards, STR_KBD_MICROSOFT_NATURAL));
-	pc_kbdc.out_clock_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_clk_w));
-	pc_kbdc.out_data_cb().set("keybc", FUNC(at_keyboard_controller_device::kbd_data_w));
+	pc_kbdc.out_clock_cb().set(m_mb, FUNC(at_mb_device::kbd_clk_w));
+	pc_kbdc.out_data_cb().set(m_mb, FUNC(at_mb_device::kbd_data_w));
 
 	/* internal ram */
 	RAM(config, m_ram).set_default_size("3712K");