Configuring an M1 CPU with Modsoft
870 USE 101 10 V.2 229
Setting the Time, Continued
Option 2 Go online and set the register values individually, using the followin g guidelines an d
procedure for setting the status bits and setting the time bits. The CPU must be
running while you are setting the bits.
Setting the
Status Bits The control register (4
x
) uses its four most significant bits to report status:
Setting the Time
Bits The following table shows how the registers handle time-of-day clock data, where
register 4
x
is the first register in the block reserved for the clock:
Continued on next page
Control Register
1514131211109876543210
1 = error
1 = All clock values have been set
1 = Clock values are being read
1 = Clock values are being set
Register Data Content
4
x
The control register
4
x
+ 1 Day of the week (Sunday = 1, Monday = 2, etc.)
4
x
+ 2 Month of the year (Jan = 1, Feb = 2, etc.)
4
x
+ 3 Day of the month (1...31)
4
x
+ 4 Year (00...99)
4
x
+ 5 Hour in military time (0...23)
4
x
+ 6 Minute (0...59)
4
x
+ 7 Second (0...59)