668-0003-C Rabbit Semiconductor, 668-0003-C Datasheet - Page 125

• Manufacturer Part Number: 668-0003-C
• Description: IC CPU RABBIT2000 30MHZ 100PQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 668-0003-C

• Rohs Status: RoHS non-compliant
• Processor Type: Rabbit 2000 8-Bit
• Speed: 30MHz
• Voltage: 2.7V, 3V, 3.3V, 5V
• Mounting Type: Surface Mount
• Package / Case: 100-MQFP, 100-PQFP
• Features: -
• Other names: 316-1004; 668-0003

Two features related to asynchronous and clocked serial communication were added to the
Rabbit 2000 serial port hardware in revisions A–C to improve and simplify asynchronous
serial and clocked serial communication. See Section B.2.3 for more information.
The Rabbit has four on-chip serial ports designated A, B, C, and D. All the ports can perform
asynchronous serial communications at high baud rates. Ports A and B have the additional
capabilities of being able to operate as clocked ports and of being switchable to alternate I/O
pins. Port A has the special capability of being usable to perform a cold boot of the micropro-
cessor system.
Figure 12-1 shows a block diagram of the serial ports.
The individual serial ports are capable of operating at baud rates in excess of 500,000 bps
in the asynchronous mode, and 8 times faster than that in the synchronous mode. Either 7
or 8 data bits may be transmitted and received in the asynchronous mode. The so-called
"9th" bit or address bit mode of operation is also supported. Parity and multiple stop bits
are not directly supported by the hardware, but may be accomplished with suitable pro-
gramming techniques.
Chapter 12 Rabbit Serial Ports
Input to timers
perclk/2 or
perclk/2
prescaled
Timer A5
Figure 12-1. Block Diagram of Rabbit Serial Ports
Timer A4
Timer A6
Timer A7
12. R
Serial Port A
Serial Port B
Serial Port C
Serial Port D
ABBIT
S
ERIAL
Tx
Tx
Tx
Tx
Rx
Rx
Rx
Rx
CLKA
CLKB
Alternate I/O
Alternate I/O
P
ORTS
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