Data Sheet Revision 1.0

Page 4

OX16C954 rev B

OXFORD SEMICONDUCTOR LTD.

14.5

TTL Clock Mode ........................................................................................................................................................................36

14.6

External 1x Clock Mode...........................................................................................................................................................36

14.7

Crystal Oscillator Circuit.........................................................................................................................................................36

15 ADDITIONAL FEATURES ................................................................................................................................................................37

15.1

Additional Status Register ‘ASR’...........................................................................................................................................37

15.2

FIFO Fill levels ‘TFL & RFL’.....................................................................................................................................................37

15.3

Additional Control Register ‘ACR’.........................................................................................................................................37

15.4

Transmitter Trigger Level ‘TTL’..............................................................................................................................................39

15.5

Receiver Interrupt. Trigger Level ‘RTL’.................................................................................................................................39

15.6

Flow Control Levels ‘FCL’ & ‘FCH’ ........................................................................................................................................39

15.7

Device Identification Registers ..............................................................................................................................................39

15.8

Clock Select Register ‘CKS’....................................................................................................................................................40

15.9

Nine-bit Mode Register ‘NMR’.................................................................................................................................................40

15.10

Modem Disable Mask ‘MDM’ ..............................................................................................................................................41

15.11

Readable FCR ‘RFC’ ............................................................................................................................................................41

15.12

Good-data status register ‘GDS’ .......................................................................................................................................41

15.13

DMA Status Register ‘DMS’................................................................................................................................................42

15.14

Port Index Register ‘PIX’.....................................................................................................................................................42

15.15

Clock Alteration Register ‘CKA’ ........................................................................................................................................42

16 OPERATING CONDITIONS..............................................................................................................................................................43

17 DC ELECTRICAL CHARACTERISTICS .........................................................................................................................................44

17.1

5V Operation..............................................................................................................................................................................44

17.2

3.3V Operation...........................................................................................................................................................................45

18 AC ELECTRICAL CHARACTERISTICS .........................................................................................................................................46

18.1

5V Operation..............................................................................................................................................................................46

18.2

3.3V Operation...........................................................................................................................................................................47

19 TIMING WAVEFORMS......................................................................................................................................................................48

20 PACKAGE INFORMATION...............................................................................................................................................................50

21 ORDERING INFORMATION.............................................................................................................................................................52

NOTES ......................................................................................................................................................................................................53

CONTACT DETAILS................................................................................................................................................................................54