20-668-0003 Rabbit Semiconductor, 20-668-0003 Datasheet - Page 107

• Manufacturer Part Number: 20-668-0003
• Description: IC CPU RABBIT2000 30MHZ 100PQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 20-668-0003

• 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
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 30 MHz
• Operating Supply Voltage: 0 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Number Of Programmable I/os: 40
• Number Of Timers: 8 & 10 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 20-668-0003; 316-1062

9.2 Parallel Port B
Parallel Port B, shown in Table 9-4, has six inputs and two outputs when used exclusively
as a parallel port.
When the slave port is enabled, parallel port lines PB2–PB7 are assigned to various slave
port functions. However, it is still possible to read PB0–PB5 using the Port B data register
even when lines PB2–PB7 are used for the slave port. It is also possible to read the signal
driving PB6 and PB7 (this signal is on the signaling lines from the slave port logic).
Regardless of whether the slave port is enabled, PB0 reflects the input of the pin unless
serial port B has its internal clock enabled, which causes this line to be driven by the serial
port clock. PB1 reflects the input of the pin unless serial port A has its internal clock
enabled.
On reset the output bits 6 and 7 are reset and the value output on pins PB6 and PB7 (pack-
age pins 99, 100) will also be low.
Chapter 9 Parallel Ports
Port B Data Register
Read
Write
Register Name
Echo
drive
PB7
Table 9-4. Parallel Port B Data Register PBDR (adr = 0x040)
Bit 7
Echo
drive
PB6
Bit 6
Table 9-3. Parallel Port B Registers
PB5 in
x
Bit 5
PBDR
Mnemonic
PB4 in
x
Bit 4
PB3 in
x
0x40
Bit 3
I/O address
PB2 in
x
Bit 2
R/W
R/W
PB1 in
x
Bit 1
00xxxxxx
PB0 in
x
Reset
Bit 0
101