Z84C9008VSG Zilog, Z84C9008VSG Datasheet - Page 63

• Manufacturer Part Number: Z84C9008VSG
• Description: IC 8MHZ Z80 KIO 84-PLCC
• Manufacturer: Zilog
• Series: Z80r

Specifications of Z84C9008VSG

• Processor Type: Z80
• Features: Serial/Parallel Input/Output, Counter/Timer Circuit
• Speed: 8MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 84-LCC (J-Lead)
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Mounting Style: SMD/SMT
• Cpu Speed: 8MHz
• Digital Ic Case Style: LCC
• No. Of Pins: 84
• Supply Voltage Range: 5V
• Operating Temperature Range: 0°C To +70°C
• Svhc: No SVHC (18-Jun-2010)
• Rohs Compliant: Yes
• Base Number: 84
• Clock Frequency: 8MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Z80 CPU
User’s Manual
43
the 8-bit Op Code. This is possible because only eight separate addresses
located in page zero of the external memory may be specified. Program
jumps may also be achieved by loading register HL, IX, or IY directly
into the PC, thus allowing the jump address to be a complex function of
the routine being executed.
The input/output group of instructions in the Z80 allow for a wide range
of transfers between external memory locations or the general-purpose
CPU registers, and the external I/O devices. In each case, the port number
is provided on the lower eight bits of the address bus during any I/O
transaction. One instruction allows this port number to be specified by the
second byte of the instruction while other Z80 instructions allow it to be
specified as the content of the C register. One major advantage of using
the C register as a pointer to the I/O device is that it allows multiple I/O
ports to share common software driver routines. This advantage is not
possible when the address is part of the Op Code if the routines are stored
in ROM. Another feature of these input instructions is the automatic
setting of the flag register, making additional operations unnecessary to
determine the state of the input data. The parity state is one example.
The Z80 CPU includes single instructions that can move blocks of data
(up to 256 bytes) automatically to or from any I/O port directly to any
memory location. In conjunction with the dual set of general-purpose
registers, these instructions provide fast I/O block transfer rates. The
power of this I/O instruction set is demonstrated by the Z80 CPU
providing all required floppy disk formatting on double-density floppy
disk drives on an interrupt-driven basis. For example, the CPU provides
the preamble, address, data, and enables the CRC codes.
Finally, the basic CPU control instructions allow various options and
modes. This group includes instructions such as setting or resetting the
interrupt enable flip-flop or setting the mode of interrupt response.
UM008005-0205
Z80 CPU Instruction Description