Toshiba TLCS-900/H1 Series Manual page 122

3.6.5 Internal Boot ROM Control
This section describes the built-in boot ROM.
For the specification of S/W in boot ROM, refer to 3.20 boot ROM sections.
(1) BOOT mode
BOOT mode is started by following AM1 and AM0 pins condition with reset.
AM1
(2) Boot ROM memory map
Boot ROM consists of an 8-Kbyte masked ROM and is assigned to address 3FE000H
to 3FFFFFH.
(3) Reset/interrupt address conversion circuit
The Reset/interrupt vector area is assigned to FFFF00H to FFFFEFH ((A) area) in
the TLCS-900/H1.
Since the boot ROM is assigned to another area, a reset/interrupt vector address
conversion circuit is provided.
In BOOT mode, the reset/interrupt vector area is assigned to 3FFF00H to 3FFFEFH
((B) area). Following boot sequence, the area can be changed to (A) area by setting
BROMCR<VACE> to "0". Therefore, (A) area can be used only for the application
system program.
This <VACE> is initialized to "1" in BOOT mode. In any other starting mode, this
register has no effect.
Note: As the last 16-byte area (FFFFF0H to FFFFFFH) is reserved for an emulator, this
area is not changed by the <VACE> register.
AM0
0 0
0 1
1 0
1 1
000000H
Internal I/O, RAM
006000H
3FE000H
Internal boot ROM
(8 Kbytes)
3FFF00H
400000H
FFFF00H
92CH21-120
Start mode
Don't use this setting
Start with 16-bit data bus
Start with 32-bit data bus
Start with boot (32-bit internal MROM)
(B) Reset/interrupt
vector area
(256 bytes)
(A) Reset/interrupt
vector area (256 bytes)
TMP92CH21
2009-06-19