MC68307V Datasheet, PDF (16/34 Pages) Motorola, Inc – Technical Summary Integrated Multiple-Bus Processor

UART Programming Model
The programming model for the UART module is listed in Table 10. The FC (function code) column indicates
whether a register is restricted to supervisor access (S) or programmable to exist in either supervisor or user
space (S/U). The address column contains the offset from the base address (MBASE) contained in the SIM07
MBAR.
Table 10. UART Module Registers
Address
FC
Register Name
MBASE+$101 S/U Do not access byte $100
UART mode register (UMR1,UMR2)
MBASE+$103 S/U Do not access byte $102 UART status/clock select register (USR,UCSR)
MBASE+$105 S/U Do not access byte $104
UART command register (UCR)
MBASE+$107 S/U Do not access byte $106 (read) UART receive buffer (UTB, URB)
MBASE+$107 S/U Do not access byte $106 (write) UART transmit buffer (UTB, URB)
MBASE+$109 S/U Do not access byte $108 (read) UART CTS change register (UCCR)
MBASE+$109 S/U Do not access byte $108 (write) UART auxiliary control register (UACR)
MBASE+$10B S/U Do not access byte $10A (read) UART interrupt status register (UISR)
MBASE+$10B S/U Do not access byte $10A (write) UART interrupt mask register (UIMR)
MBASE+$10D S/U Do not access byte $10C
Baud rate gen prescaler msb (UBG1)
MBASE+$10F S/U Do not access byte $10E
Baud rate gen prescaler lsb (UBG2)
MBASE+$119 S/U Do not access byte $118
UART interrupt vector register (UIVR)
MBASE+$11B S/U Do not access byte $11A UART CTS unlatched input port (UCP)
MBASE+$11D S/U Do not access byte $11C UART RTS output bit set cmd (URBS)
MBASE+$11F S/U Do not access byte $11E UART RTS output bit reset cmd (URBR)
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MC68307 TECHNICAL INFORMATION
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