Micro Technic PV-1800 - Manual (Page 14)

Users Manual & Installation Guide
PV- 1800: Power supply module with GSM MODEM
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REG_CNTMODE (base+6): Counter configuration (read/write)
The counter starts at 0000h after system reset. It cannot be reset or reloaded from software.
Bits: 000000 cc
cc = counter mode (read/write):
00 = counter disabled, DI0 and DI1 are ignored
01 = counts rising edges of DI0
10 = counts falling edges of DI0
11 = quadrature counter on DI0 and DI1
REG_MODEM (base+7): Modem status and on/off control (read/write)
Bits: 00000 vlo
v: (read only) 1 = VIO voltage (2.75V) on, 0=off.
l: (read only) Modem LED status. 0=LED off, 1=LED on.
o: (read/write) Force on/off. Writing '1' to this bit pulls the modem on/off pin
low. To turn the modem on or off, you should write '1' to this bit, wait at
least two seconds, and then write '0' to this bit.
The PV-1800 has logic that automatically turns the modem on at system reset.
REG_UPS (base+8): UPS status (read only)
The UPS status inputs have no other function than being readable here.
Bits: ab000000
a: UPS status1 input from external UPS logic
b: UPS status2 input from external UPS logic
REG_UPSSHDN (base+9): UPS delayed shutdown timer (read/write)
This register holds the number of seconds until the external UPS logic is told to
turn off power.
The UPS_PWROFF output is low (0V) when the system should run normally, and high (3.3V)
when external UPS circuitry should turn off power.
FFh: Idle, no delayed shutdown is in progress. UPS_PWROFF is low.
00h: Delay expired, UPS_PWROFF is high.
Other values: Delay in progress, the counter decrements towards 00h. UPS_PWROFF is low.
A delayed shutdown is initiated by writing the desired number of seconds to this
register. A delayed shutdown in progress can be modified (by writing a new value
to this register), cancelled (by writing FFh), or you can turn off immediately by
writing 00h.