System Overview
Am186™CC/CH/CU Microcontrollers User’s Manual
3-19
DRAM
[CAS0]
[CAS1]
MCS2
MCS1
O
Column Address Strobes 0–1: When either the upper or lower
chip select regions are configured for DRAM, these pins provide
the column address strobe signals to the DRAM. The CAS
signals can be used to perform byte writes in a manner similar
to WLB and WHB, respectively, i.e., [CAS0] corresponds to the
low byte (WLB) and [CAS1] corresponds to the high byte (WHB).
[RAS0]
LCS
O
Row Address Strobe 0: When the lower chip select region is
configured to DRAM, this pin provides the row address strobe
signal to the lower DRAM bank.
[RAS1]
[MCS3]
PIO5
O
Row Address Strobe 1: When the upper chip select region is
configured to DRAM, this pin provides the row address strobe
signal to the upper DRAM bank.
INTERRUPTS
INT5–INT0
—
STI
Maskable Interrupt Requests 0–8 indicate to the
microcontroller that an external interrupt request has occurred.
If the individual pin is not masked, the microcontroller transfers
program execution to the location specified by the associated
interrupt vector in the microcontroller’s interrupt vector table.
Interrupt requests are synchronized internally and can be edge-
triggered or level-triggered. The interrupt polarity is
programmable.To guarantee interrupt recognition for edge-
triggered interrupts, the user should hold the interrupt source for
a minimum of five system clocks. A second interrupt from the
same source is not recognized until after an acknowledge of the
first.
The board designer is responsible for properly terminating the
INT8–INT0 inputs.
[INT6]
PIO19
[INT7]
PIO7
[INT8]
[PWD]
PIO6
Table 3-7
Signal Descriptions (Continued)
Signal Name
1
Multiplexed
Signal(s)
Type Description
Summary of Contents for Am186 CC
Page 1: ...Am186 CC CH CU Microcontrollers User s Manual Order 21914B...
Page 4: ...iv Am186 CC CH CU Microcontrollers User s Manual...
Page 18: ...Table of Contents xviii Am186 CC CH CU Microcontrollers User s Manual...
Page 24: ...Introduction xxiv Am186 CC CH CU Microcontrollers User s Manual...
Page 40: ...Architectural Overview 1 16 Am186 CC CH CU Microcontrollers User s Manual...
Page 86: ...System Overview 3 36 Am186 CC CH CU Microcontrollers User s Manual...
Page 92: ...Emulator Support 4 6 Am186 CC CH CU Microcontrollers User s Manual...
Page 112: ...DRAM Controller 6 8 Am186 CC CH CU Microcontrollers User s Manual...
Page 134: ...Interrupts 7 22 Am186 CC CH CU Microcontrollers User s Manual...
Page 186: ...Programmable I O Signals 9 8 Am186 CC CH CU Microcontrollers User s Manual...
Page 200: ...Watchdog Timer 11 6 Am186 CC CH CU Microcontrollers User s Manual...
Page 232: ...Asynchronous Serial Ports UARTs 13 24 Am186 CC CH CU Microcontrollers User s Manual...
Page 242: ...Synchronous Serial Port SSI 14 10 Am186 CC CH CU Microcontrollers User s Manual...
Page 264: ...High Level Data Link Control HDLC 15 22 Am186 CC CH CU Microcontrollers User s Manual...
Page 332: ...Universal Serial Bus USB 18 34 Am186 CC CH CU Microcontrollers User s Manual...
Page 348: ...Register Summary A 16 Am186 CC CH CU Microcontrollers User s Manual...
Page 376: ...Index Index 18 Am186 CC CH CU Microcontrollers User s Manual...