tmp88f846ug TOSHIBA Semiconductor CORPORATION, tmp88f846ug Datasheet - Page 32

• Manufacturer Part Number: tmp88f846ug
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

2.1 Functions of the CPU Core
2. Functional Description
Address Trap Control Register
Address Trap Control Code Register
(1F94H)
(1F95H)
ATKEY
ATAS
2.1.5.2
Note: Read-modify-write instructions, such as a bit manipulation, cannot access ATAS or ATKEY register because these register
RESET
are write only.
internal RAM,SFR or DBR area, the device generats an internal reset.
The address trap is permited initially and the internal reset is generated by fetching from internal
RAM,SFR or DBR area. If the address trap is prohibited, instructions in the internal RAM area can be
executed.
ATKEY
ATAS
7
7
-
Adress Trap Reset
If the CPU should start looping for reasons of noise, etc. and attempts to fetch instructions from the
The addess trap permission/prohibition is set by the address trap reset control register (ATAS,ATKEY).
Note 1: In development tools, address trap cannot be prohibited in the internal RAM,SFR or DBR area with
Note 2: While the SWI instruction at an address immediately before the address trap area is executing, the
Development tool setting
VDD
the address trap control registers. When using development tools, even if the address trap permis-
sion/prohibition setting is changed in the user’s program, this change is ineffective. To execute
instructions from the RAM area, development tools must be set accordingly.
program counter is incremented to point to the next address in the address trap area; an address trap
is therefore taken immediately.
6
Select the address trap
permission / prohibition
6
Write control code to prohibit
address trap
-
5
5
-
Figure 2-11 Reset Circuit
Warming up circuit
4
4
-
Malfunction reset
output circuit
0: Permit address trap
1: Prohibit address trap
D2H: Address trap prohibition code
Others: Ineffective
3
3
-
(It may be available after setting control code for ATKEY register)
Page 22
2
2
-
Internal reset
1
1
-
ATAS
0
0
(initial value: **** ***0)
(initial value: **** ****)
Watchdog timer reset
Address trap reset
System clock reset
Voltage detection 1
Voltage detection 2
Power on reset
Trimming data reset
TMP88F846UG
Write
Write
only
only