Rainbow Electronics ATAR862-3 - Manual (Page 23)

23
ATAR862-3
4556B–4BMCU–02/03
Figure 18. Voltage Monitor
Voltage Monitor Control/
Status Register Primary register address: "F’hex"
VM2: V oltage monitor M ode bit 2
VM1: V oltage monitor M ode bit 1
VM0: V oltage monitor M ode bit 0
VIM V oltage I nterrupt M ask bit
VIM = 0, voltage monitor interrupt is enabled
VIM = 1, voltage monitor interrupt is disabled
VMS V oltage M onitor S tatus bit
VMS = 0, the voltage at the comparator input is below V
Ref
VMS = 1, the voltage at the comparator input is above V
Ref
V
DD
VM2
Voltage monitor
VM1 VM0 VIM
VMS - - res
OUT
IN
BP41/
VMI
INT7
VMC :
VMST :
Bit 3 Bit 2 Bit 1 Bit 0
VMC: Write VM2 VM1 VM0 VIM Reset value: 1111b
VMST: Read – – reserved VMS Reset value: xx11b
VM2 VM1 VM0 Function
1 1 1 Disable voltage monitor
1 1 0
External (VIM-input), internal reference threshold (1.3 V), interrupt
with negative slope
1 0 1 Not allowed
1 0 0
External (VMI-input), internal reference threshold (1.3 V), interrupt
with positive slope
0 1 1
Internal (supply voltage), high threshold (3.0 V), interrupt with
negative slope
0 1 0
Internal (supply voltage), middle threshold (2.6 V), interrupt with
negative slope
0 0 1
Internal (supply voltage), low threshold (2.2 V), interrupt with
negative slope
0 0 0 Not allowed