20-668-0003 Rabbit Semiconductor, 20-668-0003 Datasheet - Page 108

• 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

9.3 Parallel Port C
Parallel port C, shown in Table 9-6, has four inputs and four outputs. The even-numbered
ports, PC0, PC2, PC4, and PC6, are outputs. The odd-numbered ports, PC1, PC3, PC5,
and PC7, are inputs. When the data register is read, bits 1,3,5,7 return the value of the volt-
age on the pin. Bits 0,2,4,6 return the value of the signal driving the output buffers. The
signal driving the output buffers and the value of the output pin are normally the same.
Either the Port C data register is driving these pins or one of the serial port transmit lines is
driving the pin. The bits set in the PCFR Parallel Port C Function Register identify
whether the data register or the serial port transmit lines were driving the pins.
Parallel port C shares its pins with the four serial ports. The parallel port input pins may
also serve as serial port inputs. (Serial ports A and B can alternately use bits 7 and 5
respectively in Port D as inputs, and the source of the serial port inputs for these serial
ports depends on the setup of the corresponding serial port control register.) When serving
as serial inputs, the data lines can still be read from the parallel port C data register. The
parallel port outputs can be selected to be serial port outputs by storing bits in the corre-
sponding positions of the Port C Function register (PCFR). When a parallel port output pin
is selected to be a serial port output, the value stored in the data register is ignored. On
reset the active (even-numbered) function register bits and data register bits are zeroed.
This causes the port to output zeros on the four output bits.
102
Port C Data Register
Port C Function Register
PCDR (r)
adr = 0x050
PCDR (w)
adr = 0x050
PCFR (w)
adr = 0x055
Register Name
Table 9-6. Parallel Port C Data Register and Function Register
PC7 in
x
x
Bit 7
Table 9-5. Parallel Port C Registers
Echo
drive
PC6
Drive
TXA
Bit 6
PC5 in
x
x
Bit 5
PCDR
PCFR
Mnemonic
Echo
drive
PC4
Drive
TXB
Bit 4
Rabbit 2000 Microprocessor User’s Manual
0x50
0x55
I/O address
PC3 in
x
x
Bit 3
Echo
drive
PC2
Drive
TXC
Bit 2
R/W
W
R/W
PC1 in
x
x
Bit 1
x0x0x0x0
x0x0x0x0
Reset
Echo
drive
PC0
Drive
TXD
Bit 0