ox16c954 ETC-unknow, ox16c954 Datasheet - Page 42

• Manufacturer Part Number: ox16c954
• Description: High Performance Quad Uart With 128-byte Fifos Intel / Motorola Bus Interface
• Manufacturer: ETC-unknow

15.13 DMA Status Register ‘DMS’
The DMS register is located at offset 0x11 of the ICR. This
allows the internal TXRDY# and RXRDY# lines to be
permanently deasserted, and the current internal status to
be monitored. This mainly has applications for testing.
DMS[0]: RxRdy Status
Read Only: set when RxRdy is asserted (pin driven low).
DMS[1]: TxRdy Status
Read Only: set when TxRdy is asserted (pin driven low).
DMS[5:2] Reserved
DMS[6]: Force RxRdy Inactive
logic 0
logic 1
DMA[7]: Force TxRdy Inactive
logic 0
logic 1
15.14 Port Index Register ‘PIX’
The PIX register is located at offset 0x12 of the ICR. This
read-only register gives the UART index. This returns 0, 1,
2 or 3 depending on which UART is being accessed.
Data Sheet Revision 1.0
OXFORD SEMICONDUCTOR LTD.
RxRdy# acts normally
RxRdy# is permanently inactive (high)
regardless of FIFO thresholds
TxRdy# acts normally
TxRdy# is permanently inactive (high)
regardless of FIFO thresholds.
15.15 Clock Alteration Register ‘CKA’
The CKA register is located at offset 0x13 of the ICR. This
register adds additional clock control mainly for
isochronous and embedded applications. The register is
effectively an enhancement to the CKS register.
This register is cleared to 0x00 after a hardware reset to
maintain compatibility with 16C550, but is unaffected by
software reset. This allows the user to select a clock mode
and then reset the channel to work-around any timing
glitches.
CKA[0]: Invert Receiver Clock
logic 0
logic 1
CKA[1]: Invert Transmitter Clock
logic 0
logic 1
CKA[2]: Invert DTR output
logic 0
logic 1
CKA[3]: Use CLKSEL as System Clock
logic 0
logic 1
receiver clock as normal
receiver clock inverted (isoc apps)
transmitter clock as normal
transmitter clock inverted (isoc apps)
DTR as normal
DTR inverted
XTLI used as system clock
CLKSEL used as system clock
OX16C954 rev B
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