+;------------------------ ISC16IS740 UART --------------------------------
+;50 RHR in Receive Holding
+;50 THR out Transmit Holding
+;51 IER in/out Interrupt Enable
+;52 IIR in Interrupt Identification
+;52 FCR out FIFO Control
+;53 LCR in/out Line Control
+;54 MCR in/out Modem Control
+;55 LSR in Line Status
+;56 MSR in Modem Status
+;57 SPR in/out Scratchpad
+;56 TCR in/out Transmission Control
+;57 TLR in/out Trigger Level
+;58 TXLVL in Transmit FIFO Level
+;59 RXLVL in Receive FIFO Level
+;5F EFCR in/out Extra Features
+;50 DLL in/out divisor latch LSB
+;51 DLH in/out divisor latch MSB
+;52 EFR in/out Enhanced Feature
+;54 XON1 in/out Xon1 word
+;55 XON2 in/out Xon2 word
+;56 XOFF1 in/out Xoff1 word
+;57 XOFF2 in/out Xoff2 word