Microcontroller Application Technology Selection (7)

Author: Chief Editor: He Limin
Publisher:
Publish Date: 1999-08-01
Features:
Fragment: — From the 196KR, there is a special port—Slaveport. It is used for parallel communication between the CPU devices. In this operation mode, 196KR connects to the main CPU in slave mode. The main CPU can access the I/O, memory, or other parallel interface devices of 196KR. Some address/data bus control signals of 196KR can be used as dual-port RAM, exchanging data between 196KR and other processors. The additional functions of 4.8XC196KR in special operation modes still retain Idle and power-down modes, as well as Once functions. 196KR has an EPROM device, model 87C196KR. Programming, in addition to automatic loading programming, slave mode, and Run-Time mode, also provides a serial port programming method for programming the internal EPROM.
Seven. Microcontrollers for Motor Control — 8XC196MX
The 196MC/MD/MH is a highly functional three-phase AC waveform generator integrated into the 196, specifically developed for variable frequency air conditioners and motor control. It has been successfully used in mid-to-high-end variable frequency air conditioners and can also be used in universal variable frequency controllers for central control. The 196MX devices include 8 to 13-channel ADCs with resolutions of 8/10 bits. Sampling time, conversion time, and sampling accuracy can all be set through software to ensure optimal sampling time and accuracy. Instructions can be set to correct the DC offset of the ADC system. The ADC port can also be used as a digital input port.
1. 8XC196MC/MH with Three-Phase Waveform Generator
The MC/MH series in the 196MX devices include a three-phase waveform generator unit, capable of controlling three-phase/single-phase AC motors and brushless DC motors. The MD version also includes a frequency generator. The three-phase PWM waveform generator (WFG) in 196MC/MH has a resolution of up to 125ns (edge-aligned mode) or 250ns (center-aligned mode). The software can control the frequency, duty cycle, and "dead time" of the WFG. Each phase of the WFG has two programmable, high-output-drive-capability, and polarity-programmable output terminals. In case of external faults, all WFG outputs can be cut off via input ports. Like other 196 devices, 196MC/MH also has EPA functionality for event monitoring and control, such as event capture and comparison. The number of EPAs in the two devices is different.
2. 8XC196MD with Frequency Generator
The 8XC196MD includes the features of 8XC196MC but replaces the waveform generator with a programmable frequency generator, which can produce continuous frequency outputs. It can be used for infrared remote control communication. The pin configuration of 196MD is slightly different from 196MC.
3. Applications of 8XC196MX
The 196MC has strong software and hardware capabilities and has been used in variable frequency air conditioners, with the indoor unit using 196MH and the outdoor unit using 196MC. The indoor unit employs FuzzyLogic operations, monitoring and calculating indoor/outdoor temperature, humidity, and personnel movement to optimally control the outdoor unit's operation and meet people's comfort requirements. A large number of analog monitoring and fixed or floating-point operations can be easily implemented on 196MX. Due to its strong capabilities, 196MX can also be used for the design of split-type variable frequency air conditioners (one-to-two or one-to-three) and central air conditioning systems for controlling fans or temperature settings in various rooms.
Eight. 8XC196NX Series with Address Space Exceeding 64Kbyte
The 196NX is a 196 series device with an address space exceeding 64Kbyte, with models 8XC196NT/8XC196NP/8XC196NU. The three devices have internal ROM capacities of 32K (NT), 24K (NU), and 4K (NP). The NU has 6 chip-select outputs, with each output's address and data buses capable of dynamically operating in multiplexed or split modes. The output buses can also insert 0 to 15 wait states, and the data bus width can be dynamically switched between 8-bit and 16-bit. When the application project has a large amount of program and data, such devices can be used. Intel also recommends using 196NX with Intel's BootBlockFlash. BootBlockFlash is a solid-state data storage device that combines EPROM, EEPROM, and Flash functions, capable of storing programs and data.
1. 8XC196NU with Frequency Multiplication Feature
The 8XC196NT and 8XC196KT have the same features, with the 4 AD input terminals on 8XC196KT being external address ports (EPROT) on 8XC196NT. The EPORT can function as external addressing lines or standard slow-speed I/O ports and can also be used in combination. The NU can control the internal phase-locked loop circuit to double or triple-frequency external crystals via external pins (PLLEN1/2), or it can control non-multiplication, allowing the internal maximum operating frequency to reach 50MHz. The NP is pin-to-pin compatible with NU except for the lack of a frequency multiplication pin, and it has hardware resources similar to NU.
2. Other Special-Purpose Microcontrollers in the 8XC196 Series
In automotive applications, 196 also has some special devices that can be used, such as the 196CX, which integrates hardware specifically designed for automotive applications, such as CAN bus on 196CX and J1850 communication protocol on 196LX. For example, the previously mentioned 196KR has been used in electronic fuel injection control for automobiles.
Nine. Application Notes
1. Differences in ADCs Among 8XC196 Models
The ADCs in different 196 models have slight differences. In 8X9X, there is only a single 10-bit converter with a fixed conversion time; in 196KB, there are two operating speeds, fast and slow; 196KC adds 8-bit or 10-bit sampling resolution, with 8-bit resolution providing faster sampling speed, and 196KC can also set sampling and conversion times to ensure sufficient sampling accuracy. 196KR includes all the features of 196KCA/D and also includes bias correction and internal reference voltage and ANGND conversion, intended to more effectively correct analog system errors. 196MC includes all the functions of 196KR and expands the ADC channels to 14, allowing more analog signals to be connected without additional components.
2. Connection with Flash Memory
Typically, 80C196 programs require an external EPROM or other program memory. Intel also provides Flash with DIP package pin compatibility, which can replace EPROM and does not require a UV eraser, with programming speeds faster than EPROM. Additionally, Intel provides BootBlockFlash, which includes a program area where programs can be stored, with the remaining space used as Flash. With software support, online program modification can be achieved.
Excerpted from Electronic Technology Monthly, 199X, Issue 1.