Table 4-2

Initial Register State After Reset

 

 

 

 

 

 

Value at

 

 

 

Register Name

Mnemonic

Reset

 

 

Comments

 

 

 

 

Processor Status Flags

F

F002h

Interrupts disabled

 

 

 

 

 

 

Instruction Pointer

IP

0000h

 

 

 

 

 

 

 

 

Code Segment

 

CS

FFFFh

Boot address is FFFF0h

 

 

 

 

 

Data Segment

 

DS

0000h

DS = ES = SS = 0000h

 

 

 

 

 

 

 

Extra Segment

 

ES

0000h

 

 

 

 

 

 

 

 

 

 

Stack Segment

 

SS

0000h

 

 

 

 

 

 

 

 

Processor Release Level

PRL

XXxxh

 

PRL XX = Revision (lower half-word is undefined)

 

 

 

 

 

Peripheral Control Block

RELREG

20FFh

 

Peripheral control block located at FF00h in I/O space

Relocation

 

 

 

 

and interrupt controller in Master mode

 

 

 

 

 

Memory Partition

MDRAM

0000h

 

Refresh base address is 00000h

 

 

 

 

 

 

Enable RCU

 

EDRAM

0000h

 

Refresh disabled, counter = 0

 

 

 

 

 

 

Upper Memory Chip Select

UMCS

F03Bh

 

 

active for 64K from F0000h to FFFFFh, 3 wait

 

UCS

 

 

 

 

states, external Ready signal required

 

 

 

 

 

 

Low Memory Chip Select

LMCS

Undefined

 

 

 

 

 

 

 

Serial Port Control

SPCT

0000h

Serial port interrupts disabled, no loopback, no break,

 

 

 

 

BRKVAL low, no parity, word length = 7, 1 stop bit,

 

 

 

 

transmitter and receiver disabled

 

 

 

 

 

 

 

PIO Direction 1

 

PIODIR1

FFFFh

 

 

 

 

 

 

 

 

 

 

PIO Mode 1

 

PIOMODE1

0000h

 

 

 

 

 

 

 

 

 

 

PIO Direction 0

 

PIODIR0

FC0Fh

 

 

 

 

 

 

 

 

 

 

PIO Mode 0

 

PIOMODE0

0000h

 

 

 

 

 

 

 

Serial Port Interrupt Control

SPICON

001Fh

Serial port interrupt masked, priority 7

 

 

 

 

Watchdog Timer Interrupt

WDCON

000Fh

Watchdog timer interrupt masked, priority 7

Control

 

 

 

 

 

 

 

 

 

 

 

INT4 Control

 

I4CON

000Fh

Int4 interrupt masked, edge-triggered, priority 7

 

 

 

 

 

INT3 Control

 

I3CON

000Fh

Int3 interrupt masked, edge-triggered, priority 7

 

 

 

 

 

INT2 Control

 

I2CON

000Fh

Int2 interrupt masked, edge-triggered, priority 7

 

 

 

 

 

INT1 Control

 

I1CON

000Fh

Int1 interrupt masked, edge-triggered, priority 7

 

 

 

 

 

INT0 Control

 

I0CON

000Fh

Int0 interrupt masked, edge-triggered, priority 7

 

 

 

 

DMA1 Interrupt Control

DMA1CON

000Fh

DMA1 interrupts masked, edge-triggered, priority 7

 

 

 

 

DMA0 Interrupt Control

DMA0CON

000Fh

DMA0 interrupts masked, edge-triggered, priority 7

 

 

 

 

Timer Interrupt Control

TCUCON

000Fh

Timer interrupts masked, edge-triggered, priority 7

 

 

 

 

 

In-Service

 

INSERV

0000h

No interrupts are in-service

 

 

 

 

 

 

Priority Mask

 

PRIMSK

0007h

 

Allow all interrupts based on priority

 

 

 

 

 

Interrupt Mask

 

IMASK

07FDh

All interrupts masked (off)

 

 

 

 

Synchronous Serial Control

SSC

0000h

SCLK = 1/2 CLKOUTA, no data enabled

 

 

 

 

Synchronous Serial Status

SSS

0000h

Synchronous serial port not busy, no errors, no transmit

 

 

 

 

or receive completed.

 

 

 

 

 

 

 

DMA 1 Control

 

D1CON

FFF9h

 

 

 

 

 

 

 

 

 

 

DMA 0 Control

 

D0CON

FFF9h

 

 

 

 

 

 

 

 

 

 

Note:

Registers not listed in this table are undefined at reset.

Peripheral Control Block

4-9

Page 67
Image 67
AMD Am188TMER, Am186TMER user manual Registers not listed in this table are undefined at reset