--- /dev/null
+; vi:filetype=z80:
+
+UART_REG_MODEA equ $00 ; MR1A/MR2A
+UART_REG_STATA equ $01 ; SRA (rd)
+UART_REG_CSELA equ $01 ; CSRA (wr)
+UART_REG_CMDA equ $02 ; CRA (wr)
+UART_REG_DATAA equ $03 ; RBA (rd) / TBA (wr)
+
+UART_REG_MODEB equ $08 ; MR1B/MR2B
+UART_REG_STATB equ $09 ; SRB (rd)
+UART_REG_CSELB equ $09 ; CSRB (wr)
+UART_REG_CMDB equ $0a ; CRB (wr)
+UART_REG_DATAB equ $0b ; RBB (rd) / TBB (wr)
+
+UART_REG_IPCR equ $04 ; (rd)
+UART_REG_AUXCTL equ $04 ; ACR (wr)
+UART_REG_ISTAT equ $05 ; ISR (rd)
+UART_REG_IMASK equ $05 ; IMR (wr)
+UART_REG_COUNTH equ $06 ; CUR (rd)
+UART_REG_COUNTL equ $07 ; CLR (rd)
+UART_REG_CTSETH equ $06 ; CTUR (wr)
+UART_REG_CTSETL equ $07 ; CTLR (wr)
+
+UART_REG_IVEC equ $0c ; IVR
+UART_REG_IPORT equ $0d ; (rd)
+UART_REG_OPCR equ $0d ; (wr)
+UART_REG_CSTART_CMD equ $0e ; (rd)
+UART_REG_CSTOP_CMD equ $0f ; (rd)
+UART_REG_OSET equ $0e ; (wr)
+UART_REG_OCLR equ $0f ; (wr)
+
+
+UART_M1_5BIT equ $00
+UART_M1_6BIT equ $01
+UART_M1_7BIT equ $02
+UART_M1_8BIT equ $03
+UART_M1_PAREVEN equ $00
+UART_M1_PARODD equ $04
+UART_M1_NOPAR equ $10
+UART_M1_IRQ_RDY equ $00
+UART_M1_IRQ_FULL equ $40
+UART_M1_RX_RTS equ $80
+
+; stop bit count goes in low nibble of MODE2 register
+UART_M2_STOP1 equ $07
+UART_M2_CTS equ $10
+UART_M2_TX_RTS equ $20
+UART_M2_ECHO equ $40
+UART_M2_LOOP_LOCAL equ $80
+UART_M2_LOOP_REMOTE equ $c0
+
+UART_CSEL_TX_300 equ $04
+UART_CSEL_RX_300 equ $40
+UART_CSEL_TX_9600 equ $0b
+UART_CSEL_RX_9600 equ $b0
+UART_CSEL_TX_38400_19200 equ $0c
+UART_CSEL_RX_38400_19200 equ $c0
+UART_CSEL_TX_TIMER equ $0d
+UART_CSEL_RX_TIMER equ $d0
+
+UART_STAT_RXRDY equ $01
+UART_STAT_FFULL equ $02
+UART_STAT_TXRDY equ $04
+UART_STAT_TXEMPTY equ $08
+UART_STAT_ERR_OVR equ $10
+UART_STAT_ERR_PAR equ $20
+UART_STAT_ERR_FRM equ $40
+UART_STAT_ERR_BRK equ $80
+
+UART_CMD_RX_ON equ $01
+UART_CMD_RX_OFF equ $02
+UART_CMD_TX_ON equ $04
+UART_CMD_TX_OFF equ $08
+UART_CMD_RST_MPTR equ $10
+UART_CMD_RST_RX equ $20
+UART_CMD_RST_TX equ $30
+UART_CMD_RST_ERR equ $40
+UART_CMD_RST_BRKINT equ $50
+UART_CMD_START_BRK equ $60
+UART_CMD_STOP_BRK equ $70
+
+UART_OPCR_OP2_TXCA16 equ $01
+UART_OPCR_OP2_TXA equ $02
+UART_OPCR_OP2_RXA equ $03
+UART_OPCR_OP3_CTR equ $04
+UART_OPCR_OP3_TXB equ $08
+UART_OPCR_OP3_RXB equ $0c
+UART_OPCR_OP4_RXRDYA equ $10
+UART_OPCR_OP5_RXRDYB equ $20
+UART_OPCR_OP6_TXRDYA equ $40
+UART_OPCR_OP7_TXRDYB equ $80