|
|
 |
|
|
|
The NEC V20 Processor
|
|
The NEC V20 is a 16-bit CMOS microprocessor with 8-bit external data bus, object-code and pin-compatible with
the Intel 8088. The V20 runs at the same speed as the 8088, but it's slightly
faster due to internal improvements - dual internal 16-bit data bus, faster effective address calculation,
better loop counter/shift register implementation, and some others. The V20 includes Intel 8080 emulation mode,
in which it can execute all of the 8080 instructions. Native NEC V20 instruction set includes all 8086/8088
instructions, new instructions from the 80186/80188 microprocessor, and instructions unique to V20 -
bit processing, packed BCD instructions and special instructions for switching the processor to 8080
emulation mode and back.
The V20 is almost the same as the NEC V30 with the exception that the V30 has a 16-bit data bus. |
|
|
|
|
|
The NEC V30 Processor
|
|
The NEC V30 is a 16-bit CMOS microprocessor, object-code and pin-compatible with
the Intel 8088. The V30 runs at the same speed as the 8088, but it's
10% - 30% faster (depending on application) due to internal improvements - dual internal 16-bit data bus, faster
effective address calculation, better loop counter/shift register implementation, and some others.
The V30 includes Intel 8080 emulation mode,
in which it can execute all of the 8080 instructions. Native NEC V30 instruction set includes all 8086/8088
instructions, new instructions from the 80186/80188 microprocessor, and instructions unique to V30 -
bit processing, packed BCD instructions and special instructions for switching the processor to 8080
emulation mode and back.
The V30 is almost the same as the NEC V20 with the exception that the V20 has an 8-bit data bus. |
|
|
|
|
|
The NEC V50 Processor
|
|
The NEC V50 is a 16-bit embedded microprocessor compatible with NEC V30. The V50 has all of the features of the V30 (8080 emulation, new instructions, low-power consumption, standby mode, and others), and at the same time integrates many peripherals on the chip - clock generator, DRAM refresh control, timers/counters, bus interface and bus arbitration units, asynchronous serial I/O channel, wait-state generator and 8-input interrupt control unit.
It is typically used as a processor for embedded devices. Network switches from various manufacturers use the V50. |
|
|
|
|
|
