System Overview
3-18
Am186™CC/CH/CU Microcontrollers User’s Manual
PCS0
[PIO13]
{USBSEL1}
O
Peripheral Chip Selects 0–7 indicate to the system that an
access is in progress to the corresponding region of the
peripheral address block (either I/O or memory address space).
The base address of the peripheral address block is
programmable. PCS7–PCS0 are three-stated with pullup
resistors during bus-hold or reset conditions.
Unlike the UCS and LCS chip selects that operate relative to the
earlier timing of the nonmultiplexed A address bus, the PCS
outputs assert with the multiplexed AD address and data bus
timing.
PCS1
[PIO14]
{USBSEL2}
PCS2
—
PCS3
—
[PCS4]
PIO3
[CLKSEL2]
[PCS5]
PIO2
[PCS6]
PIO32
[PCS7]
PIO31
UCS
{ONCE}
O
Upper Memory Chip Select indicates to the system that a
memory access is in progress to the upper memory block. The
base address and size of the upper memory block are
programmable up to 512 Kbytes. UCS is three-stated with a
weak pullup during bus-hold or reset conditions.
The UCS can be configured for an 8-bit or 16-bit bus size out of
reset. For additional information, see the {UCSX8} pin
description in Table 3-5 on page 3-7.
After reset, UCS is active for the 64-Kbyte memory range from
F0000h to FFFFFh, including the reset address of FFFF0h.
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...