* miscellaneous definitions
HResMaxX equ 639 high resolution X limit
HResMaxY equ 191 high resolution Y limit
MousData equ $0008 arbitrary choice for mouse data area ($0008-$000E)
PcktSize equ 3 number of bytes in mouse data packet
SyncData equ %01000000 initial mouse data byte pattern

* 6551 register definitions
 org 0
DataReg rmb 1 receive/transmit data
StatReg rmb 1 IRQ/DSR/DCD/error status (read only)
PRstReg equ StatReg programmed reset (write only)
CmdReg rmb 1 command (parity/echo/Tx IRQ/Rx IRQ/DTR)
CtrlReg rmb 1 control (stop bits/word length/Rx clock/baud rate)

* Status bit definitions
Stat.IRQ equ %10000000 IRQ occurred
Stat.DSR equ %01000000 current DSR input level (0=enabled, 1=disabled)
Stat.DCD equ %00100000 current DCD input level (0=enabled, 1=disabled)
Stat.TxE equ %00010000 Tx register empty
Stat.RxF equ %00001000 Rx register full
Stat.Ovn equ %00000100 overrun error
Stat.Frm equ %00000010 framing error
Stat.Par equ %00000001 parity error

Stat.Err equ Stat.Ovn!Stat.Frm!Stat.Par status error bits
Stat.Flp equ $00 all status bits active when set
Stat.Msk equ Stat.RxF!Stat.Ovn!Stat.Frm!Stat.Par active IRQ bits

* Command bit definitions
Cmd.Par equ %11100000 see parity table below
Cmd.Echo equ %00010000 Rx echo (0=disabled, 1=enabled)
Cmd.TxIC equ %00001100 see Tx IRQ control table below
Cmd.RxIE equ %00000010 Rx IRQ enable (0=enabled, 1=disabled)
Cmd.DTR equ %00000001 DTR output (0=disabled, 1=enabled)

* parity table
Par.None equ %00000000
Par.Odd equ %00100000
Par.Even equ %01100000
Par.Mark equ %10100000
Par.Spac equ %11100000

* Tx IRQ control table
TIC.Off equ %00000000 RTS disabled, Tx IRQ disabled
TIC.On equ %00000100 RTS enabled, Tx IRQ enabled
TIC.RTS equ %00001000 RTS enabled, Tx IRQ disabled
TIC.Brk equ %00001100 RTS enabled, Tx line break

* Control bit definitions
Ctl.Stop equ %10000000 stop bits (clear=1, set=2)
Ctl.DBit equ %01100000 see data bit table below
Ctl.RClk equ %00010000 Rx clock source (0=external, 1=internal)
Ctl.Baud equ %00001111 see baud rate table below

* data bit table
DB.5 equ %01100000 five data bits per character
DB.6 equ %01000000 six data bits per character
DB.7 equ %00100000 seven data bits per character
DB.8 equ %00000000 eight data bits per character

* baud rate table
 org 0
BR.ExClk rmb 1 16x external clock
BR.00050 rmb 1 50 baud
BR.00075 rmb 1 75 baud
BR.00110 rmb 1 109.92 baud
BR.00135 rmb 1 134.58 baud
BR.00150 rmb 1 150 baud
BR.00300 rmb 1 300 baud
BR.00600 rmb 1 600 baud
BR.01200 rmb 1 1200 baud
BR.01800 rmb 1 1800 baud
BR.02400 rmb 1 2400 baud
BR.03600 rmb 1 3600 baud
BR.04800 rmb 1 4800 baud
BR.07200 rmb 1 7200 baud
BR.09600 rmb 1 9600 baud
BR.19200 rmb 1 19200 baud

* Buffer (0,u only) bit definitions
B.Butn1 equ %00100000 button #1 (left, 1 = pressed)
B.Butn2 equ %00010000 button #2 (right, 1 = pressed)

B.Butns equ B.Butn1!B.Butn2 mask for all buttons


* mouse static data area definitions
 org 0
Buffer rmb 2 Rx buffer for mouse data (must start at 0,u)
Counter rmb 1 Rx data counter
CrntXPos rmb 2 mouse X position (0 to HResMaxX)
CrntYPos rmb 2 mouse Y position (0 to HResMaxY*2)