Force SYS68K/CPU-30 R4, Техническое справочное руководство

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FGA Boot Software SYS68K/CPU-30 R4 Technical Reference Manual
Page 178
Figure 6: Boot up procedure
The Boot ROM (at address FFE0.0000
16
) is mapped to 0000.0000
16
.
The CPU loads its initial stack pointer (SSP) and initial program counter (PC)
from locations 0
16
and 4
16
.
is it correct ?
Y N
%
Set SRAM parameters to default values.
Actions / State
Install exception handler and execute C startup code.
Check reset condition and leave FGA-002’s boot mode. Now the Boot ROM
resides at address FFE0.0000
16
. Check if Abort Switch is asserted
➞
abort
.
Read board ID from port.
Initialize CPU registers, enable caches.
Initialize the front-panel serial I/O port 1.
Initialize the PIT devices.
Identify board features (interfaces) and read serial ID-ROM.
Determine the processor’s clock frequency.
Determine capacity of main memory.
Calculate checksum of SRAM parameters (register and system values).
Check if the board is system controller via bit 0 of the "Slot-1 Status Register".
This bit is set by the slot-1 autodetection or SW8-1.
bit 0 == 1?
N Y
%
Board is System Controller, set bit 2 (ARBITER) in CTL1 value.
Read front-panel rotary switches and store to SRAM.