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-rw-r--r--src/mame/includes/bbc.h74
1 files changed, 37 insertions, 37 deletions
diff --git a/src/mame/includes/bbc.h b/src/mame/includes/bbc.h
index d21d24839f1..b53a469ccd4 100644
--- a/src/mame/includes/bbc.h
+++ b/src/mame/includes/bbc.h
@@ -313,22 +313,22 @@ public: // HACK FOR MC6845
bool m_lk19_ic37_paged_rom; // BBC Master Paged ROM/RAM select IC37
/*
- ACCCON
- b7 IRR 1=Causes an IRQ to the processor
- b6 TST 1=Selects &FC00-&FEFF read from OS-ROM
- b5 IFJ 1=Internal 1 MHz bus
- 0=External 1MHz bus
- b4 ITU 1=Internal Tube
- 0=External Tube
- b3 Y 1=Read/Write HAZEL &C000-&DFFF RAM
- 0=Read/Write ROM &C000-&DFFF OS-ROM
- b2 X 1=Read/Write LYNNE
- 0=Read/WRITE main memory &3000-&8000
- b1 E 1=Causes shadow if VDU code
- 0=Main all the time
- b0 D 1=Display LYNNE as screen
- 0=Display main RAM screen
- ACCCON is a read/write register
+ ACCCON
+ b7 IRR 1=Causes an IRQ to the processor
+ b6 TST 1=Selects &FC00-&FEFF read from OS-ROM
+ b5 IFJ 1=Internal 1 MHz bus
+ 0=External 1MHz bus
+ b4 ITU 1=Internal Tube
+ 0=External Tube
+ b3 Y 1=Read/Write HAZEL &C000-&DFFF RAM
+ 0=Read/Write ROM &C000-&DFFF OS-ROM
+ b2 X 1=Read/Write LYNNE
+ 0=Read/WRITE main memory &3000-&8000
+ b1 E 1=Causes shadow if VDU code
+ 0=Main all the time
+ b0 D 1=Display LYNNE as screen
+ 0=Display main RAM screen
+ ACCCON is a read/write register
*/
int m_acccon;
@@ -343,27 +343,27 @@ public: // HACK FOR MC6845
/*
- The addressable latch
- This 8 bit addressable latch is operated from port B lines 0-3.
- PB0-PB2 are set to the required address of the output bit to be set.
- PB3 is set to the value which should be programmed at that bit.
- The function of the 8 output bits from this latch are:-
-
- B0 - Write Enable to the sound generator IC
- B1 - READ select on the speech processor (B and B+)
- R/nW control on CMOS RAM (Master only)
- B2 - WRITE select on the speech processor
- DS control on CMOS RAM (Master only)
- B3 - Keyboard write enable
- B4,B5 - these two outputs define the number to be added to the
- start of screen address in hardware to control hardware scrolling:-
- Mode Size Start of screen Size No.to add B5 B4
- 0,1,2 20K &3000 12K 1 1
- 3 16K &4000 16K 0 0
- 4,5 10K &5800 (or &1800) 22K 1 0
- 6 8K &6000 (or &2000) 24K 0 1
- B6 - Operates the CAPS lock LED (Pin 17 keyboard connector)
- B7 - Operates the SHIFT lock LED (Pin 16 keyboard connector)
+ The addressable latch
+ This 8 bit addressable latch is operated from port B lines 0-3.
+ PB0-PB2 are set to the required address of the output bit to be set.
+ PB3 is set to the value which should be programmed at that bit.
+ The function of the 8 output bits from this latch are:-
+
+ B0 - Write Enable to the sound generator IC
+ B1 - READ select on the speech processor (B and B+)
+ R/nW control on CMOS RAM (Master only)
+ B2 - WRITE select on the speech processor
+ DS control on CMOS RAM (Master only)
+ B3 - Keyboard write enable
+ B4,B5 - these two outputs define the number to be added to the
+ start of screen address in hardware to control hardware scrolling:-
+ Mode Size Start of screen Size No.to add B5 B4
+ 0,1,2 20K &3000 12K 1 1
+ 3 16K &4000 16K 0 0
+ 4,5 10K &5800 (or &1800) 22K 1 0
+ 6 8K &6000 (or &2000) 24K 0 1
+ B6 - Operates the CAPS lock LED (Pin 17 keyboard connector)
+ B7 - Operates the SHIFT lock LED (Pin 16 keyboard connector)
*/
int m_b0_sound;