Emulator Support
Am186™CC/CH/CU Microcontrollers User’s Manual 4-5
4.3.2.18 S2–S0
The S2–S0 bus indicates the type of memory cycle in progress.
4.3.2.19 S6
The S6 signal is active from t
1
–t
4
on the microcontroller and signals a refresh or DMA
access.
4.3.2.20 SRDY
See “ARDY and SRDY” on page 4-3.
4.3.2.21 UCS
The system typically uses UCS as a FLASH or ROM chip select. Emulators use this to
determine when ROM accesses occur, and can intercept it for overlay memory purposes.
4.3.2.22 {UCSX8} and WLB
During processor reset, the UCSX8 pin configures the upper memory region for 8-bit
operation. The BSIZE8 signal unambiguously indicates the width of a memory region for a
given access.
4.3.2.23 WHB and WR
The emulator can intercept WHB and WR for use with overlay memory. Although most
emulators use S2–S0 to determine cycle type, some may use the WR signal to determine
when writes occur. This prevents the use of WR as a PIO when using the emulator.
4.3.2.24 WLB
4.3.2.25
WR
See “WHB and WR” .
4.3.3 Hardware-Related Considerations
■
Be sure to allow room for pucks and emulator heads on your target board.
■
The following PIO signals are multiplexed with alternate signals that may be used by
emulators: PIO8, PIO15, PIO33, PIO34, and PIO35. Consider any emulator
requirements for the alternate signals before using these pins as PIOs.
4.3.4 Comparison to Other Devices
■
Previous Am186 watchdog timer implementations required the application to disable the
watchdog timer to prevent watchdog time-outs while emulator code was executing. The
Am186CC/CH/CU watchdog timer does not have this limitation. A feature of the
watchdog timer allows ICE code to inhibit the count of the watchdog timer.
4.4 INITIALIZATION
On both external and internal reset, the following occurs:
■
Multiplexed pins used in emulation default to signals shown in Chapter 3, “System
Overview.”
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...