W79E548 Datasheet, PDF (24/79 Pages) Winbond – 8-BIT MICROCONTROLLER

W79E548/W79L548
SADEN: This register enables the Automatic Address Recognition feature of the Serial port 0. When
a bit in the SADEN is set to 1, the same bit location in SADDR will be compared with the
incoming serial data. When SADEN.n is 0, then the bit becomes a "don't care" in the
comparison. This register enables the Automatic Address Recognition feature of the Serial
port 0. When all the bits of SADEN are 0, interrupt will occur for any incoming address.
Power Management Register
Bit:
7
6
5
4
3
2
1
0
-
-
-
-
-
ALE-OFF
-
DME0
Mnemonic: PMR
Address: C4h
ALE0FF: This bit disables the expression of the ALE signal on the device pin during all on-board
program and data memory accesses. External memory accesses will automatically enable
ALE independent of ALEOFF.
0 = ALE expression is enable; 1 = ALE expression is disable
DME0: This bit determines the on-chip MOVX SRAM to be enabled or disabled. Set this bit to 1 will
enable the on-chip 1KB MOVX SRAM.
Status Register
Bit:
7
6
5
4
3
2
1
0
-
HIP
LIP
-
-
-
-
-
Mnemonic: STATUS
Address: C5h
HIP: High Priority Interrupt Status. When set, it indicates that software is servicing a high priority
interrupt. This bit will be cleared when the program executes the corresponding RETI
instruction.
LIP: Low Priority Interrupt Status. When set, it indicates that software is servicing a low priority
interrupt. This bit will be cleared when the program executes the corresponding RETI
instruction.
Timed Access
Bit:
7
TA.7
6
TA.6
5
TA.5
4
TA.4
3
TA.3
2
TA.2
1
TA.1
0
TfA.0
Mnemonic: TA
Address: C7h
TA: The Timed Access register controls the access to protected bits. To access protected bits, the
user must first write AAH to the TA. This must be immediately followed by a write of 55H to TA.
Now a window is opened in the protected bits for three machine cycles, during which the user can
write to these bits.
Timer 2 Control
Bit:
7
6
5
4
3
2
1
0
TF2 EXF2 RCLK TCLK EXEN2 TR2 C / T2 CP / RL2
Mnemonic: T2CON
Address: C8h
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