XR17V358IB-0A-EVB Datasheet, PDF (15/68 Pages) Exar Corporation – HIGH PERFORMANCE OCTAL PCI EXPRESS UART

XR17V358
REV. 1.0.4
HIGH PERFORMANCE OCTAL PCI EXPRESS UART
1.3 Device Internal Register Sets
The Device Configuration Registers and the eight individual UART Configuration Registers of the V358
occupy 8K of PCI bus memory address space. These addresses are offset onto the basic memory address, a
value loaded into the Memory Base Address Register (BAR) in the PCI local bus configuration register set. The
UART Configuration Registers are mapped into 8 address blocks where each UART channel occupies 1024
bytes memory space for its own registers that include the 16550 compatible registers. The Device
Configuration Registers are accessible from all UART channels. However, not all bits can be controlled by all
channels. The UART channel can only control the 8XMODE, 4XMODE, RESET and SLEEP register bits that
apply to that particular channel. For example, this prevents channel 0 from accidentally resetting channel 1.
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