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Diffstat (limited to 'src/mess/drivers/trs80.c')
-rw-r--r--src/mess/drivers/trs80.c46
1 files changed, 23 insertions, 23 deletions
diff --git a/src/mess/drivers/trs80.c b/src/mess/drivers/trs80.c
index 606b9df4a45..7d5ff95779c 100644
--- a/src/mess/drivers/trs80.c
+++ b/src/mess/drivers/trs80.c
@@ -5,7 +5,7 @@ TRS80 memory map
0000-2fff ROM R D0-D7
3000-37ff ROM on Model III R D0-D7
- unused on Model I
+ unused on Model I
37de UART status R/W D0-D7
37df UART data R/W D0-D7
37e0 interrupt latch address (lnw80 = for the realtime clock)
@@ -16,7 +16,7 @@ TRS80 memory map
37e5 select disk drive 2 W
37e7 select disk drive 3 W
37e0-37e3 floppy motor W D0-D3
- or floppy head select W D3
+ or floppy head select W D3
37e8 send a byte to printer W D0-D7
37e8 read printer status R D7
37ec-37ef FDC WD179x R/W D0-D7
@@ -42,10 +42,10 @@ It is assumed that the TRS80L2 UART setup is identical to the System80, apart fr
Due to the above, the only working emulated UART is for the Model 3.
Cassette baud rates: Model I level I - 250 baud
- Model I level II and all clones - 500 baud
- Model III/4 - 500 and 1500 baud selectable at boot time
- - When it says "Cass?" press L for 500 baud, or Enter otherwise.
- LNW-80 - 500 baud @1.77MHz and 1000 baud @4MHz.
+ Model I level II and all clones - 500 baud
+ Model III/4 - 500 and 1500 baud selectable at boot time
+ - When it says "Cass?" press L for 500 baud, or Enter otherwise.
+ LNW-80 - 500 baud @1.77MHz and 1000 baud @4MHz.
I/O ports
FF:
@@ -92,29 +92,29 @@ Model 4 - C0-CF = hard drive (optional)
- 80-8F hires graphics (optional)
About the ht1080z - This was made for schools in Hungary. Each comes with a BASIC extension roms
- which activated Hungarian features. To activate - start emulation - enter SYSTEM
- Enter /12288 and the extensions will be installed and you are returned to READY.
- The ht1080z is identical to the System 80, apart from the character rom.
- The ht1080z2 has a modified extension rom and character generator.
+ which activated Hungarian features. To activate - start emulation - enter SYSTEM
+ Enter /12288 and the extensions will be installed and you are returned to READY.
+ The ht1080z is identical to the System 80, apart from the character rom.
+ The ht1080z2 has a modified extension rom and character generator.
About the RTC - The time is incremented while ever the cursor is flashing. It is stored in a series
- of bytes in the computer's work area. The bytes are in a certain order, this is:
- seconds, minutes, hours, year, day, month. On a model 1, the seconds are stored at
- 0x4041, while on the model 4 it is 0x4217. A reboot always sets the time to zero.
+ of bytes in the computer's work area. The bytes are in a certain order, this is:
+ seconds, minutes, hours, year, day, month. On a model 1, the seconds are stored at
+ 0x4041, while on the model 4 it is 0x4217. A reboot always sets the time to zero.
Model 4 memory organisation -
- Mode 0: ROM=0-37E7 and 37EA-3FFF; Printer=37E8-37E9; Keyboard=3800-3BFF; Video=3C00-3FFF
- Mode 1: Keyboard and Video as above; 0-3FFF read=ROM and write=RAM
- Mode 2: Keyboard=F400-F7FF; Video=F800-FFFF; the rest is RAM
- Mode 3: All RAM
- In the "maincpu" memory map, the first 64k is given to the ROM, keyboard, printer and video,
- while the second 64k is RAM that is switched in as needed. The area from 4800-FFFF
- is considered a "black hole", any writes to there will disappear.
- The video is organised as 2 banks of 0x400 bytes, except in Mode 2 where it becomes contiguous.
+ Mode 0: ROM=0-37E7 and 37EA-3FFF; Printer=37E8-37E9; Keyboard=3800-3BFF; Video=3C00-3FFF
+ Mode 1: Keyboard and Video as above; 0-3FFF read=ROM and write=RAM
+ Mode 2: Keyboard=F400-F7FF; Video=F800-FFFF; the rest is RAM
+ Mode 3: All RAM
+ In the "maincpu" memory map, the first 64k is given to the ROM, keyboard, printer and video,
+ while the second 64k is RAM that is switched in as needed. The area from 4800-FFFF
+ is considered a "black hole", any writes to there will disappear.
+ The video is organised as 2 banks of 0x400 bytes, except in Mode 2 where it becomes contiguous.
Model 4P - is the same as Model 4 except:
- - ROM is only 0000-0FFF, while 1000-37FF is given over to RAM
- - There is no cassette support in hardware.
+ - ROM is only 0000-0FFF, while 1000-37FF is given over to RAM
+ - There is no cassette support in hardware.
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