AM186 datasheet(7/112 Pages) AMD

7 / 112 page

Am186TMER and Am188TMER Microcontrollers Data Sheet

DRAF

Chip-Select Unit ......................................................................................................................... 49

Chip-Select Timing ......................................................................................................... 49

Ready and Wait-State Programming ............................................................................. 49

Memory Maps ................................................................................................................ 50

Chip-Select Overlap ....................................................................................................... 51

Upper Memory Chip Select ............................................................................................ 51

Low Memory Chip Select ............................................................................................... 51

Midrange Memory Chip Selects ..................................................................................... 51

Peripheral Chip Selects ................................................................................................. 52

Internal Memory ......................................................................................................................... 52

Interaction with External RAM ........................................................................................ 52

Emulator and Debug Modes .......................................................................................... 52

Refresh Control Unit .................................................................................................................. 53

Interrupt Control Unit ................................................................................................................. 53

Programming the Interrupt Control Unit ......................................................................... 53

Timer Control Unit ...................................................................................................................... 53

Watchdog Timer ........................................................................................................................ 54

Direct Memory Access ............................................................................................................... 54

DMA Operation .............................................................................................................. 55

Asynchronous Serial Port/DMA Transfers ..................................................................... 55

DMA Channel Control Registers .................................................................................... 55

DMA Priority ...................................................................................................................55

Asynchronous Serial Port .......................................................................................................... 56

DMA Transfers through the Serial Port .......................................................................... 56

Synchronous Serial Interface ..................................................................................................... 56

Four-Pin Interface .......................................................................................................... 57

Programmable I/O (PIO) Pins ....................................................................................................57

Low-Voltage Operation .............................................................................................................. 59

Low-Voltage Standard ................................................................................................... 59

Power Savings ............................................................................................................... 59

Input/Output Circuitry ..................................................................................................... 59

Absolute Maximum Ratings .......................................................................................................60

Operating Ranges ...................................................................................................................... 60

DC Characteristics Over Commercial and Industrial Operating Ranges ................................... 60

Thermal Characteristics ............................................................................................................. 61

TQFP Package .............................................................................................................. 61

Typical Ambient Temperatures ...................................................................................... 62

Commercial and Industrial Switching Characteristics and Waveforms ...................................... 67

Key to Switching Waveforms ......................................................................................... 67

Alphabetical Key to Switching Parameter Symbols ....................................................... 68

Numerical Key to Switching Parameter Symbols .......................................................... 69