OX16C950 rev B
OXFORD SEMICONDUCTOR LTD.
PERFORMANCE COMPARISON
1
Feature
External 1x baud rate clock
Max baud rate in normal mode
Max baud rate in 1x clock mode
FIFO depth
OX16C950
Yes
15 Mbps
60 Mbps
128
16C450
No
115 kbps
n/a
1
16C550
No
115 kbps
n/a
16
16C650
No
1.5 Mbps
n/a
32
16C750
No
1 Mbps
n/a
64
Sleep mode
Auto Xon/Xoff flow
Yes
Yes
Yes
Yes
127
128
128
Yes
Yes
Yes
248
Yes
No
No
No
No
1
1
n/a
No
n/a
n/a
n/a
No
No
No
No
No
4
1
n/a
No
No
Yes
Yes
Yes
No
4
4
4
No
No
No
Yes
No
Yes
No
4
1
n/a
No
No
No
n/a
No
Auto CTS#/RTS# flow
Auto DSR#/DTR# flow
No. of Rx interrupt thresholds
No. of Tx interrupt thresholds
No. of flow control thresholds
Transmitter empty interrupt
Readable status of flow control
Readable FIFO levels
Clock prescaler options
Rx/Tx disable
No
n/a
No
2
No
Software reset
Yes
No
No
No
No
Device ID
Yes
No
No
No
No
9-bit data frames
Yes
No
No
No
No
RS485 buffer enable
Infra-red (IrDA)
Yes
Yes
No
No
No
No
No
Yes
No
No
Table 1 OX16C950 performance compared with 16C450, 16C550, 16C650 and 16C750 devices
Improvements of the OX16C950 over previous generations of PC UART:
Deeper FIFOs:
OX16C950 offers 128-byte deep FIFOs for the transmitter
Special character detection:
and receiver.
The receiver can be programmed to generate an interrupt
upon reception of a particular character value.
Higher data rates:
Transmission and reception baud rates up to 15Mbps. A
flexible clock prescaler offers division ratios of 1 to 31 7/8
in steps of 1/8 using a divide-by-“M N/8” circuitry. The
flexible prescaler allows users to select from a wide variety
of input clock frequencies as well as access to higher baud
rates whilst maintaining compatibility with existing software
drivers (see section 14.2).
Power-down:
The device can be placed in ‘sleep mode’ to conserve
power.
Readable FIFO levels:
Driver efficiency can be improved by using readable FIFO
levels.
External clock options:
Selectable trigger levels:
The receiver can accept an external 1x clock on the DSR#
input. The transmitter can accept a 1x clock on the RI#
input and/or assert its own (Nx) clock on the DTR# output.
In 1x mode, asynchronous data may be transmitted and
received at speeds up to 60Mbps (see section 14.6).
The receiver FIFO threshold can be arbitrarily
programmed. The transmitter FIFO threshold and
thresholds for automatic flow control can be programmed
to operate at a variety of trigger levels.
Additional control:
The transmitter and receiver can be independently
Automatic flow control:
The UART automatically handles either or both in-band
(software) flow control (transmitting and receiving Xon/Xoff
characters) and out-of-band (hardware) flow control using
the RTS#/CTS# or DSR#/DTR# modem control lines.
disabled.
Data Sheet Revision 1.2
Page 5
OXFORD [ OXFORD SEMICONDUCTOR ]
