71M6403
Electronic Trip Unit
SEPTEMBER 2006
Page: 20 of 75
©
2006 TERIDIAN Semiconductor Corporation
REV 1.0
FLSHCRL
0xB2
R/W
W
R/W
R
Bit 0 (
FLSH_PWE
): Program Write Enable:
0 – MOVX commands refer to XRAM Space, normal operation
(default).
1 – MOVX @DPTR,A moves A to Program Space (Flash) @ DPTR.
This bit is automatically reset after each byte is written to flash. Writes to
this bit are inhibited when interrupts are enabled.
Bit 1 (
FLSH_MEEN
): Mass Erase Enable:
0 – Mass Erase disabled (default).
1 – Mass Erase enabled.
Must be re-written for each new Mass Erase cycle.
Bit 6 (
SECURE
):
Enables security provisions that prevent external reading of flash
memory and CE program RAM. This bit is reset on chip reset and may
only be set. Attempts to write zero are ignored.
Bit 7 (
PREBOOT
):
Indicates that the preboot sequence is active.
WDI
0xE8
R/W
R/W
Only byte operations on the whole WDI register should be used
when writing
. The byte must have all bits set except the bits that are to
be cleared.
The multi-purpose register
WDI
contains the following bits:
Bit 0 (
IE_XFER
): XFER Interrupt Flag:
This flag monitors the XFER_BUSY interrupt. It is set by hardware and
must be cleared by the interrupt handler
Bit 1 (
IE_ZP8
): 0.8sec Interrupt Flag:
This flag monitors the ZP8 0.8sec interrupt. It is set by hardware and
must be cleared by the interrupt handler
INTBITS
INT0…INT6
0xF8
R
Interrupt inputs. The MPU may read these bits to see the input to
external interrupts INT0, INT1, up to INT6. These bits do not have any
memory and are primarily intended for debug use. Refer to the External
Interrupts description.
Table 10: Special Function Registers
Instruction Set
All instructions of the generic 8051 microcontroller are supported. A complete list of the instruction set and of the associated op-
codes is contained in the 64xx Software User’s Guide (SUG).
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