diff --git a/src/emu/machine/mc6843.c b/src/emu/machine/mc6843.c
index c2bb4a68197..9426def4033 100644
--- a/src/emu/machine/mc6843.c
+++ b/src/emu/machine/mc6843.c
@@ -507,8 +507,8 @@ READ8_MEMBER( mc6843_device::read )
 	{
 		int cmd = m_CMR & 0x0f;
 
-		LOG(( "%f $%04x mc6843_r: data input cmd=%s(%i), pos=%i/%i, GCR=%i, ",
-				machine().time().as_double(), machine().firstcpu->pcbase( ),
+		LOG(( "%f %s mc6843_r: data input cmd=%s(%i), pos=%i/%i, GCR=%i, ",
+				machine().time().as_double(), machine().describe_context(),
 				mc6843_cmd[cmd], cmd, m_data_idx,
 				m_data_size, m_GCR ));
 
@@ -561,7 +561,7 @@ READ8_MEMBER( mc6843_device::read )
 		{
 			/* XXX TODO: other read modes */
 			data = m_data[0];
-			logerror( "$%04x mc6843 read in unsupported command mode %i\n", machine().firstcpu->pcbase( ), cmd );
+			logerror( "%s mc6843 read in unsupported command mode %i\n", machine().describe_context(), cmd );
 		}
 
 		LOG(( "data=%02X\n", data ));
@@ -571,15 +571,15 @@ READ8_MEMBER( mc6843_device::read )
 
 	case 1: /* Current-Track Address Register (CTAR) */
 		data = m_CTAR;
-		LOG(( "%f $%04x mc6843_r: read CTAR %i (actual=%i)\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ), data,
+		LOG(( "%f %s mc6843_r: read CTAR %i (actual=%i)\n",
+				machine().time().as_double(), machine().describe_context(), data,
 				floppy_drive_get_current_track( floppy_image( ) ) ));
 		break;
 
 	case 2: /* Interrupt Status Register (ISR) */
 		data = m_ISR;
-		LOG(( "%f $%04x mc6843_r: read ISR %02X: cmd=%scomplete settle=%scomplete sense-rq=%i STRB=%i\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ), data,
+		LOG(( "%f %s mc6843_r: read ISR %02X: cmd=%scomplete settle=%scomplete sense-rq=%i STRB=%i\n",
+				machine().time().as_double(), machine().describe_context(), data,
 				(data & 1) ? "" : "not-" , (data & 2) ? "" : "not-",
 				(data >> 2) & 1, (data >> 3) & 1 ));
 
@@ -604,8 +604,8 @@ READ8_MEMBER( mc6843_device::read )
 			m_STRA |= 0x40;
 
 		data = m_STRA;
-		LOG(( "%f $%04x mc6843_r: read STRA %02X: data-rq=%i del-dta=%i ready=%i t0=%i wp=%i trk-dif=%i idx=%i busy=%i\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ), data,
+		LOG(( "%f %s mc6843_r: read STRA %02X: data-rq=%i del-dta=%i ready=%i t0=%i wp=%i trk-dif=%i idx=%i busy=%i\n",
+				machine().time().as_double(), machine().describe_context(), data,
 				data & 1, (data >> 1) & 1, (data >> 2) & 1, (data >> 3) & 1,
 				(data >> 4) & 1, (data >> 5) & 1, (data >> 6) & 1, (data >> 7) & 1 ));
 		break;
@@ -613,8 +613,8 @@ READ8_MEMBER( mc6843_device::read )
 
 	case 4: /* Status Register B (STRB) */
 		data = m_STRB;
-		LOG(( "%f $%04x mc6843_r: read STRB %02X: data-err=%i CRC-err=%i dta--mrk-err=%i sect-mrk-err=%i seek-err=%i fi=%i wr-err=%i hard-err=%i\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ), data,
+		LOG(( "%f %s mc6843_r: read STRB %02X: data-err=%i CRC-err=%i dta--mrk-err=%i sect-mrk-err=%i seek-err=%i fi=%i wr-err=%i hard-err=%i\n",
+				machine().time().as_double(), machine().describe_context(), data,
 				data & 1, (data >> 1) & 1, (data >> 2) & 1, (data >> 3) & 1,
 				(data >> 4) & 1, (data >> 5) & 1, (data >> 6) & 1, (data >> 7) & 1 ));
 
@@ -625,13 +625,13 @@ READ8_MEMBER( mc6843_device::read )
 
 	case 7: /* Logical-Track Address Register (LTAR) */
 		data = m_LTAR;
-		LOG(( "%f $%04x mc6843_r: read LTAR %i (actual=%i)\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ), data,
+		LOG(( "%f %s mc6843_r: read LTAR %i (actual=%i)\n",
+				machine().time().as_double(), machine().describe_context(), data,
 				floppy_drive_get_current_track( floppy_image( ) ) ));
 		break;
 
 	default:
-		logerror( "$%04x mc6843 invalid read offset %i\n", machine().firstcpu->pcbase( ), offset );
+		logerror( "%s mc6843 invalid read offset %i\n", machine().describe_context(), offset );
 	}
 
 	return data;
@@ -645,8 +645,8 @@ WRITE8_MEMBER( mc6843_device::write )
 		int cmd = m_CMR & 0x0f;
 		int FWF = (m_CMR >> 4) & 1;
 
-		LOG(( "%f $%04x mc6843_w: data output cmd=%s(%i), pos=%i/%i, GCR=%i, data=%02X\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ),
+		LOG(( "%f %s mc6843_w: data output cmd=%s(%i), pos=%i/%i, GCR=%i, data=%02X\n",
+				machine().time().as_double(), machine().describe_context(),
 				mc6843_cmd[cmd], cmd, m_data_idx,
 				m_data_size, m_GCR, data ));
 
@@ -663,7 +663,7 @@ WRITE8_MEMBER( mc6843_device::write )
 				/* end of sector write */
 				device_t* img = floppy_image( );
 
-				LOG(( "%f $%04x mc6843_w: write sector %i\n", machine().time().as_double(), machine().firstcpu->pcbase( ), m_data_id ));
+				LOG(( "%f %s mc6843_w: write sector %i\n", machine().time().as_double(), machine().describe_context(), m_data_id ));
 
 				floppy_drive_write_sector_data(
 					img, m_side, m_data_id,
@@ -727,7 +727,7 @@ WRITE8_MEMBER( mc6843_device::write )
 					UINT8 track  = m_data[1];
 					UINT8 sector = m_data[3];
 					UINT8 filler = 0xe5; /* standard Thomson filler */
-					LOG(( "%f $%04x mc6843_w: address id detected track=%i sector=%i\n", machine().time().as_double(), machine().firstcpu->pcbase( ), track, sector));
+					LOG(( "%f %s mc6843_w: address id detected track=%i sector=%i\n", machine().time().as_double(), machine().describe_context(), track, sector));
 					floppy_drive_format_sector( img, m_side, sector, track, 0, sector, 0, filler );
 				}
 				else
@@ -749,15 +749,15 @@ WRITE8_MEMBER( mc6843_device::write )
 		else
 		{
 			/* XXX TODO: other write modes */
-			logerror( "$%04x mc6843 write %02X in unsupported command mode %i (FWF=%i)\n", machine().firstcpu->pcbase( ), data, cmd, FWF );
+			logerror( "%s mc6843 write %02X in unsupported command mode %i (FWF=%i)\n", machine().describe_context(), data, cmd, FWF );
 		}
 		break;
 	}
 
 	case 1: /* Current-Track Address Register (CTAR) */
 		m_CTAR = data;
-		LOG(( "%f $%04x mc6843_w: set CTAR to %i %02X (actual=%i) \n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ), m_CTAR, data,
+		LOG(( "%f %s mc6843_w: set CTAR to %i %02X (actual=%i) \n",
+				machine().time().as_double(), machine().describe_context(), m_CTAR, data,
 				floppy_drive_get_current_track( floppy_image( ) ) ));
 		break;
 
@@ -765,8 +765,8 @@ WRITE8_MEMBER( mc6843_device::write )
 	{
 		int cmd = data & 15;
 
-		LOG(( "%f $%04x mc6843_w: set CMR to $%02X: cmd=%s(%i) FWF=%i DMA=%i ISR3-intr=%i fun-intr=%i\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ),
+		LOG(( "%f %s mc6843_w: set CMR to $%02X: cmd=%s(%i) FWF=%i DMA=%i ISR3-intr=%i fun-intr=%i\n",
+				machine().time().as_double(), machine().describe_context(),
 				data, mc6843_cmd[cmd], cmd, (data >> 4) & 1, (data >> 5) & 1,
 				(data >> 6) & 1, (data >> 7) & 1 ));
 
@@ -812,36 +812,36 @@ WRITE8_MEMBER( mc6843_device::write )
 		m_SUR = data;
 
 		/* assume CLK freq = 1MHz (IBM 3740 compatibility) */
-		LOG(( "%f $%04x mc6843_w: set SUR to $%02X: head settling time=%fms, track-to-track seek time=%f\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ),
+		LOG(( "%f %s mc6843_w: set SUR to $%02X: head settling time=%fms, track-to-track seek time=%f\n",
+				machine().time().as_double(), machine().describe_context(),
 				data, 4.096 * (data & 15), 1.024 * ((data >> 4) & 15) ));
 		break;
 
 	case 4: /* Sector Address Register (SAR) */
 		m_SAR = data & 0x1f;
-		LOG(( "%f $%04x mc6843_w: set SAR to %i (%02X)\n", machine().time().as_double(), machine().firstcpu->pcbase( ), m_SAR, data ));
+		LOG(( "%f %s mc6843_w: set SAR to %i (%02X)\n", machine().time().as_double(), machine().describe_context(), m_SAR, data ));
 		break;
 
 	case 5: /* General Count Register (GCR) */
 		m_GCR = data & 0x7f;
-		LOG(( "%f $%04x mc6843_w: set GCR to %i (%02X)\n", machine().time().as_double(), machine().firstcpu->pcbase( ), m_GCR, data ));
+		LOG(( "%f %s mc6843_w: set GCR to %i (%02X)\n", machine().time().as_double(), machine().describe_context(), m_GCR, data ));
 		break;
 
 	case 6: /* CRC Control Register (CCR) */
 		m_CCR = data & 3;
-		LOG(( "%f $%04x mc6843_w: set CCR to %02X: CRC=%s shift=%i\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ), data,
+		LOG(( "%f %s mc6843_w: set CCR to %02X: CRC=%s shift=%i\n",
+				machine().time().as_double(), machine().describe_context(), data,
 				(data & 1) ? "enabled" : "disabled", (data >> 1) & 1 ));
 		break;
 
 	case 7: /* Logical-Track Address Register (LTAR) */
 		m_LTAR = data & 0x7f;
-		LOG(( "%f $%04x mc6843_w: set LTAR to %i %02X (actual=%i)\n",
-				machine().time().as_double(), machine().firstcpu->pcbase( ), m_LTAR, data,
+		LOG(( "%f %s mc6843_w: set LTAR to %i %02X (actual=%i)\n",
+				machine().time().as_double(), machine().describe_context(), m_LTAR, data,
 				floppy_drive_get_current_track( floppy_image( ) ) ));
 		break;
 
 	default:
-		logerror( "$%04x mc6843 invalid write offset %i (data=$%02X)\n", machine().firstcpu->pcbase( ), offset, data );
+		logerror( "%s mc6843 invalid write offset %i (data=$%02X)\n", machine().describe_context(), offset, data );
 	}
 }
diff --git a/src/emu/machine/mc6846.c b/src/emu/machine/mc6846.c
index af760b492e6..029118011c3 100644
--- a/src/emu/machine/mc6846.c
+++ b/src/emu/machine/mc6846.c
@@ -305,8 +305,8 @@ READ8_MEMBER(mc6846_device::read)
 	{
 	case 0:
 	case 4:
-		LOG (( "$%04x %f: mc6846 CSR read $%02X intr=%i (timer=%i, cp1=%i, cp2=%i)\n",
-				space.machine().firstcpu->pcbase( ), space.machine().time().as_double(),
+		LOG (( "%s %f: mc6846 CSR read $%02X intr=%i (timer=%i, cp1=%i, cp2=%i)\n",
+				machine().describe_context(), space.machine().time().as_double(),
 				m_csr, (m_csr >> 7) & 1,
 				m_csr & 1, (m_csr >> 1) & 1, (m_csr >> 2) & 1 ));
 		m_csr0_to_be_cleared = m_csr & 1;
@@ -315,15 +315,15 @@ READ8_MEMBER(mc6846_device::read)
 		return m_csr;
 
 	case 1:
-		LOG (( "$%04x %f: mc6846 PCR read $%02X\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), m_pcr ));
+		LOG (( "%s %f: mc6846 PCR read $%02X\n", machine().describe_context(), space.machine().time().as_double(), m_pcr ));
 		return m_pcr;
 
 	case 2:
-		LOG (( "$%04x %f: mc6846 DDR read $%02X\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), m_ddr ));
+		LOG (( "%s %f: mc6846 DDR read $%02X\n", machine().describe_context(), space.machine().time().as_double(), m_ddr ));
 		return m_ddr;
 
 	case 3:
-		LOG (( "$%04x %f: mc6846 PORT read $%02X\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), PORT ));
+		LOG (( "%s %f: mc6846 PORT read $%02X\n", machine().describe_context(), space.machine().time().as_double(), PORT ));
 		if ( ! (m_pcr & 0x80) )
 		{
 			if ( m_csr1_to_be_cleared )
@@ -337,11 +337,11 @@ READ8_MEMBER(mc6846_device::read)
 		return PORT;
 
 	case 5:
-		LOG (( "$%04x %f: mc6846 TCR read $%02X\n",space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), m_tcr ));
+		LOG (( "%s %f: mc6846 TCR read $%02X\n",machine().describe_context(), space.machine().time().as_double(), m_tcr ));
 		return m_tcr;
 
 	case 6:
-		LOG (( "$%04x %f: mc6846 COUNTER hi read $%02X\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), counter() >> 8 ));
+		LOG (( "%s %f: mc6846 COUNTER hi read $%02X\n", machine().describe_context(), space.machine().time().as_double(), counter() >> 8 ));
 		if ( m_csr0_to_be_cleared )
 		{
 			m_csr &= ~1;
@@ -351,7 +351,7 @@ READ8_MEMBER(mc6846_device::read)
 		return counter() >> 8;
 
 	case 7:
-		LOG (( "$%04x %f: mc6846 COUNTER low read $%02X\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), counter() & 0xff ));
+		LOG (( "%s %f: mc6846 COUNTER low read $%02X\n", machine().describe_context(), space.machine().time().as_double(), counter() & 0xff ));
 		if ( m_csr0_to_be_cleared )
 		{
 			m_csr &= ~1;
@@ -361,7 +361,7 @@ READ8_MEMBER(mc6846_device::read)
 		return counter() & 0xff;
 
 	default:
-		logerror( "$%04x mc6846 invalid read offset %i\n", space.machine().firstcpu->pcbase( ), offset );
+		logerror( "%s mc6846 invalid read offset %i\n", machine().describe_context(), offset );
 	}
 	return 0;
 }
@@ -390,8 +390,8 @@ WRITE8_MEMBER(mc6846_device::write)
 			"latched,neg-edge", "latched,neg-edge,intr",
 			"latcged,pos-edge", "latcged,pos-edge,intr"
 		};
-		LOG (( "$%04x %f: mc6846 PCR write $%02X reset=%i cp2=%s cp1=%s\n",
-				space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), data,
+		LOG (( "%s %f: mc6846 PCR write $%02X reset=%i cp2=%s cp1=%s\n",
+				machine().describe_context(), space.machine().time().as_double(), data,
 				(data >> 7) & 1, cp2[ (data >> 3) & 7 ], cp1[ data & 7 ] ));
 
 	}
@@ -404,7 +404,7 @@ WRITE8_MEMBER(mc6846_device::write)
 		update_irq();
 	}
 	if ( data & 4 )
-		logerror( "$%04x mc6846 CP1 latching not implemented\n", space.machine().firstcpu->pcbase( ) );
+		logerror( "%s mc6846 CP1 latching not implemented\n", machine().describe_context() );
 	if (data & 0x20)
 	{
 		if (data & 0x10)
@@ -414,12 +414,12 @@ WRITE8_MEMBER(mc6846_device::write)
 				m_out_cp2_func( 0, m_cp2_cpu );
 		}
 		else
-			logerror( "$%04x mc6846 acknowledge not implemented\n", space.machine().firstcpu->pcbase( ) );
+			logerror( "%s mc6846 acknowledge not implemented\n", machine().describe_context() );
 	}
 	break;
 
 	case 2:
-		LOG (( "$%04x %f: mc6846 DDR write $%02X\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), data ));
+		LOG (( "%s %f: mc6846 DDR write $%02X\n", machine().describe_context(), space.machine().time().as_double(), data ));
 		if ( ! (m_pcr & 0x80) )
 		{
 			m_ddr = data;
@@ -429,7 +429,7 @@ WRITE8_MEMBER(mc6846_device::write)
 		break;
 
 	case 3:
-		LOG (( "$%04x %f: mc6846 PORT write $%02X (mask=$%02X)\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), data,m_ddr ));
+		LOG (( "%s %f: mc6846 PORT write $%02X (mask=$%02X)\n", machine().describe_context(), space.machine().time().as_double(), data,m_ddr ));
 		if ( ! (m_pcr & 0x80) )
 		{
 			m_pdr = data;
@@ -438,12 +438,12 @@ WRITE8_MEMBER(mc6846_device::write)
 			if ( m_csr1_to_be_cleared && (m_csr & 2) )
 			{
 				m_csr &= ~2;
-				LOG (( "$%04x %f: mc6846 CP1 intr reset\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double() ));
+				LOG (( "%s %f: mc6846 CP1 intr reset\n", machine().describe_context(), space.machine().time().as_double() ));
 			}
 			if ( m_csr2_to_be_cleared && (m_csr & 4) )
 			{
 				m_csr &= ~4;
-				LOG (( "$%04x %f: mc6846 CP2 intr reset\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double() ));
+				LOG (( "%s %f: mc6846 CP2 intr reset\n", machine().describe_context(), space.machine().time().as_double() ));
 			}
 			m_csr1_to_be_cleared = 0;
 			m_csr2_to_be_cleared = 0;
@@ -458,8 +458,8 @@ WRITE8_MEMBER(mc6846_device::write)
 				"continuous", "cascaded", "continuous", "one-shot",
 				"freq-cmp", "freq-cmp", "pulse-cmp", "pulse-cmp"
 			};
-		LOG (( "$%04x %f: mc6846 TCR write $%02X reset=%i clock=%s scale=%i mode=%s out=%s\n",
-				space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), data,
+		LOG (( "%s %f: mc6846 TCR write $%02X reset=%i clock=%s scale=%i mode=%s out=%s\n",
+				machine().describe_context(), space.machine().time().as_double(), data,
 				(data >> 7) & 1, (data & 0x40) ? "extern" : "sys",
 				(data & 0x40) ? 1 : 8, mode[ (data >> 1) & 7 ],
 				(data & 1) ? "enabled" : "0" ));
@@ -493,7 +493,7 @@ WRITE8_MEMBER(mc6846_device::write)
 
 	case 7:
 		m_latch = ( ((UINT16) m_time_MSB) << 8 ) + data;
-		LOG (( "$%04x %f: mc6846 COUNT write %i\n", space.machine().firstcpu->pcbase( ), space.machine().time().as_double(), m_latch  ));
+		LOG (( "%s %f: mc6846 COUNT write %i\n", machine().describe_context(), space.machine().time().as_double(), m_latch  ));
 		if (!(m_tcr & 0x38))
 		{
 			/* timer initialization */
@@ -509,7 +509,7 @@ WRITE8_MEMBER(mc6846_device::write)
 		break;
 
 	default:
-		logerror( "$%04x mc6846 invalid write offset %i\n", space.machine().firstcpu->pcbase( ), offset );
+		logerror( "%s mc6846 invalid write offset %i\n", machine().describe_context(), offset );
 	}
 }
 
diff --git a/src/emu/machine/mc6854.c b/src/emu/machine/mc6854.c
index daaa23768bc..479352543f2 100644
--- a/src/emu/machine/mc6854.c
+++ b/src/emu/machine/mc6854.c
@@ -834,8 +834,8 @@ READ8_MEMBER( mc6854_device::read )
 	{
 	case 0: /* status register 1 */
 		update_sr1( );
-		LOG(( "%f $%04x mc6854_r: get SR1=$%02X (rda=%i,s2rq=%i,fd=%i,cts=%i,tu=%i,tdra=%i,irq=%i)\n",
-				space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), m_sr1,
+		LOG(( "%f %s mc6854_r: get SR1=$%02X (rda=%i,s2rq=%i,fd=%i,cts=%i,tu=%i,tdra=%i,irq=%i)\n",
+				space.machine().time().as_double(), machine().describe_context(), m_sr1,
 				( m_sr1 & RDA) ? 1 : 0, ( m_sr1 & S2RQ) ? 1 : 0,
 				( m_sr1 & FD ) ? 1 : 0, ( m_sr1 & CTS ) ? 1 : 0,
 				( m_sr1 & TU ) ? 1 : 0, ( m_sr1 & TDRA) ? 1 : 0,
@@ -844,8 +844,8 @@ READ8_MEMBER( mc6854_device::read )
 
 	case 1: /* status register 2 */
 		update_sr2( );
-		LOG(( "%f $%04x mc6854_r: get SR2=$%02X (ap=%i,fv=%i,ridle=%i,rabt=%i,err=%i,dcd=%i,ovrn=%i,rda2=%i)\n",
-				space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), m_sr2,
+		LOG(( "%f %s mc6854_r: get SR2=$%02X (ap=%i,fv=%i,ridle=%i,rabt=%i,err=%i,dcd=%i,ovrn=%i,rda2=%i)\n",
+				space.machine().time().as_double(), machine().describe_context(), m_sr2,
 				( m_sr2 & AP   ) ? 1 : 0, ( m_sr2 & FV  ) ? 1 : 0,
 				( m_sr2 & RIDLE) ? 1 : 0, ( m_sr2 & RABT) ? 1 : 0,
 				( m_sr2 & ERR  ) ? 1 : 0, ( m_sr2 & DCD ) ? 1 : 0,
@@ -856,13 +856,13 @@ READ8_MEMBER( mc6854_device::read )
 	case 3:
 	{
 		UINT8 data = rfifo_pop( );
-		LOG(( "%f $%04x mc6854_r: get data $%02X\n",
-				space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), data ));
+		LOG(( "%f %s mc6854_r: get data $%02X\n",
+				space.machine().time().as_double(), machine().describe_context(), data ));
 		return data;
 	}
 
 	default:
-		logerror( "$%04x mc6854 invalid read offset %i\n", space.machine().firstcpu->pcbase( ), offset );
+		logerror( "%s mc6854 invalid read offset %i\n", machine().describe_context(), offset );
 	}
 	return 0;
 }
@@ -875,16 +875,16 @@ WRITE8_MEMBER( mc6854_device::write )
 	{
 	case 0: /* control register 1 */
 		m_cr1 = data;
-		LOG(( "%f $%04x mc6854_w: set CR1=$%02X (ac=%i,irq=%c%c,%sreset=%c%c)\n",
-				space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), m_cr1,
+		LOG(( "%f %s mc6854_w: set CR1=$%02X (ac=%i,irq=%c%c,%sreset=%c%c)\n",
+				space.machine().time().as_double(), machine().describe_context(), m_cr1,
 				AC ? 1 : 0,
 				RIE ? 'r' : '-', TIE ? 't' : '-',
 				DISCONTINUE ? "discontinue," : "",
 				RRESET ? 'r' : '-', TRESET ? 't' : '-'
 				));
 		if ( m_cr1 & 0xc )
-			logerror( "$%04x mc6854 DMA not handled (CR1=$%02X)\n",
-					space.machine().firstcpu->pcbase( ), m_cr1 );
+			logerror( "%s mc6854 DMA not handled (CR1=$%02X)\n",
+					machine().describe_context(), m_cr1 );
 		if ( DISCONTINUE )
 		{
 			/* abort receive FIFO but keeps shift register & synchro */
@@ -912,16 +912,16 @@ WRITE8_MEMBER( mc6854_device::write )
 		{
 			/* control register 3 */
 			m_cr3 = data;
-			LOG(( "%f $%04x mc6854_w: set CR3=$%02X (lcf=%i,aex=%i,idl=%i,fdse=%i,loop=%i,tst=%i,dtr=%i)\n",
-					space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), m_cr3,
+			LOG(( "%f %s mc6854_w: set CR3=$%02X (lcf=%i,aex=%i,idl=%i,fdse=%i,loop=%i,tst=%i,dtr=%i)\n",
+					space.machine().time().as_double(), machine().describe_context(), m_cr3,
 					LCF ? (CEX ? 16 : 8) : 0,  AEX ? 1 : 0,
 					IDL0 ? 0 : 1, FDSE ? 1 : 0, LOOP ? 1 : 0,
 					TST ? 1 : 0, DTR ? 1 : 0
 					));
 			if ( LOOP )
-				logerror( "$%04x mc6854 loop mode not handled (CR3=$%02X)\n", space.machine().firstcpu->pcbase( ), m_cr3 );
+				logerror( "%s mc6854 loop mode not handled (CR3=$%02X)\n", machine().describe_context(), m_cr3 );
 			if ( TST )
-				logerror( "$%04x mc6854 test mode not handled (CR3=$%02X)\n", space.machine().firstcpu->pcbase( ), m_cr3 );
+				logerror( "%s mc6854 test mode not handled (CR3=$%02X)\n", machine().describe_context(), m_cr3 );
 
 			m_out_dtr_func( DTR ? 1 : 0 );
 
@@ -930,14 +930,14 @@ WRITE8_MEMBER( mc6854_device::write )
 		{
 			/* control register 2 */
 			m_cr2 = data;
-			LOG(( "%f $%04x mc6854_w: set CR2=$%02X (pse=%i,bytes=%i,fmidle=%i,%s,tlast=%i,clr=%c%c,rts=%i)\n",
-					space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), m_cr2,
+			LOG(( "%f %s mc6854_w: set CR2=$%02X (pse=%i,bytes=%i,fmidle=%i,%s,tlast=%i,clr=%c%c,rts=%i)\n",
+					space.machine().time().as_double(), machine().describe_context(), m_cr2,
 					PSE ? 1 : 0,  TWOBYTES ? 2 : 1,  FMIDLE ? 1 : 0,
 					FCTDRA ? "fc" : "tdra", TLAST ? 1 : 0,
 					data & 0x20 ? 'r' : '-',  data & 0x40 ? 't' : '-',
 					RTS ? 1 : 0 ));
 			if ( PSE )
-				logerror( "$%04x mc6854 status prioritization not handled (CR2=$%02X)\n", space.machine().firstcpu->pcbase( ), m_cr2 );
+				logerror( "%s mc6854 status prioritization not handled (CR2=$%02X)\n", machine().describe_context(), m_cr2 );
 			if ( TLAST )
 				tfifo_terminate( );
 			if ( data & 0x20 )
@@ -961,7 +961,7 @@ WRITE8_MEMBER( mc6854_device::write )
 		break;
 
 	case 2: /* transmitter data: continue data */
-		LOG(( "%f $%04xmc6854_w: push data=$%02X\n", space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), data ));
+		LOG(( "%f %smc6854_w: push data=$%02X\n", space.machine().time().as_double(), machine().describe_context(), data ));
 		tfifo_push( data );
 		break;
 
@@ -970,7 +970,7 @@ WRITE8_MEMBER( mc6854_device::write )
 		{
 			/* control register 4 */
 			m_cr4 = data;
-			LOG(( "%f $%04x mc6854_w: set CR4=$%02X (interframe=%i,tlen=%i,rlen=%i,%s%s)\n", space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), m_cr4,
+			LOG(( "%f %s mc6854_w: set CR4=$%02X (interframe=%i,tlen=%i,rlen=%i,%s%s)\n", space.machine().time().as_double(), machine().describe_context(), m_cr4,
 					TWOINTER ? 2 : 1,
 					TWL, RWL,
 					ABT ? ( ABTEX ? "abort-ext," : "abort,") : "",
@@ -985,14 +985,14 @@ WRITE8_MEMBER( mc6854_device::write )
 		else
 		{
 			/* transmitter data: last data */
-			LOG(( "%f $%04x mc6854_w: push last-data=$%02X\n", space.machine().time().as_double(), space.machine().firstcpu->pcbase( ), data ));
+			LOG(( "%f %s mc6854_w: push last-data=$%02X\n", space.machine().time().as_double(), machine().describe_context(), data ));
 			tfifo_push( data );
 			tfifo_terminate( );
 		}
 		break;
 
 	default:
-		logerror( "$%04x mc6854 invalid write offset %i (data=$%02X)\n", space.machine().firstcpu->pcbase( ), offset, data );
+		logerror( "%s mc6854 invalid write offset %i (data=$%02X)\n", machine().describe_context(), offset, data );
 	}
 }
 
diff --git a/src/mess/audio/mea8000.c b/src/mess/audio/mea8000.c
index a88838e5224..09e76781d06 100644
--- a/src/mess/audio/mea8000.c
+++ b/src/mess/audio/mea8000.c
@@ -525,12 +525,12 @@ READ8_MEMBER( mea8000_device::read )
 	case 1:
 		/* ready to accept next frame */
 #if 0
-		LOG(("$%04x %f: mea8000_r ready=%i\n", machine().firstcpu->pcbase(), machine().time().as_double(), accept_byte()));
+		LOG(("%s %f: mea8000_r ready=%i\n", machine().describe_context(), machine().time().as_double(), accept_byte()));
 #endif
 		return accept_byte() << 7;
 
 	default:
-		logerror("$%04x mea8000_r invalid read offset %i\n", machine().firstcpu->pcbase(), offset);
+		logerror("%s mea8000_r invalid read offset %i\n", machine().describe_context(), offset);
 	}
 	return 0;
 }
@@ -544,19 +544,19 @@ WRITE8_MEMBER( mea8000_device::write )
 		{
 			/* got pitch byte before first frame */
 			m_pitch = 2 * data;
-			LOG(("$%04x %f: mea8000_w pitch %i\n", machine().firstcpu->pcbase(), machine().time().as_double(), m_pitch));
+			LOG(("%s %f: mea8000_w pitch %i\n", machine().describe_context(), machine().time().as_double(), m_pitch));
 			m_state = MEA8000_WAIT_FIRST;
 			m_bufpos = 0;
 		}
 		else if (m_bufpos == 4)
 		{
 			/* overflow */
-			LOG(("$%04x %f: mea8000_w data overflow %02X\n", machine().firstcpu->pcbase(), machine().time().as_double(), data));
+			LOG(("%s %f: mea8000_w data overflow %02X\n", machine().describe_context(), machine().time().as_double(), data));
 		}
 		else
 		{
 			/* enqueue frame byte */
-			LOG(("$%04x %f: mea8000_w data %02X in frame pos %i\n", machine().firstcpu->pcbase(), machine().time().as_double(),
+			LOG(("%s %f: mea8000_w data %02X in frame pos %i\n", machine().describe_context(), machine().time().as_double(),
 					data, m_bufpos));
 			m_buf[m_bufpos] = data;
 			m_bufpos++;
@@ -589,8 +589,8 @@ WRITE8_MEMBER( mea8000_device::write )
 		if (stop)
 			stop_frame();
 
-		LOG(( "$%04x %f: mea8000_w command %02X stop=%i cont=%i roe=%i\n",
-				machine().firstcpu->pcbase(), machine().time().as_double(), data,
+		LOG(( "%s %f: mea8000_w command %02X stop=%i cont=%i roe=%i\n",
+				machine().describe_context(), machine().time().as_double(), data,
 				stop, m_cont, m_roe));
 
 		update_req();
@@ -598,6 +598,6 @@ WRITE8_MEMBER( mea8000_device::write )
 	}
 
 	default:
-		logerror( "$%04x mea8000_w invalid write offset %i\n", machine().firstcpu->pcbase( ), offset);
+		logerror( "%s mea8000_w invalid write offset %i\n", machine().describe_context(), offset);
 	}
 }