ADUC845_12 Datasheet, PDF (72/108 Pages) Analog Devices – MicroConverter® Multichannel 24-/16-Bit ADCs with Embedded 62 kB Flash and Single-Cycle MCU

ADuC845/ADuC847/ADuC848
Data Sheet
INTVAL—User Timer Interval Select Register
Function:
User code writes the required time interval to this register. When the 8-bit interval counter is equal to the time interval
value loaded in the INTVAL SFR, the TII bit (TIMECON.2) is set and generates an interrupt, if enabled.
SFR Address:
A6H
Power-On Default: 00H
Bit Addressable:
No
Valid Value:
0 to 255 decimal
HTHSEC—Hundredths of Seconds Time Register
Function:
This register is incremented in 1/128-second intervals once TCEN in TIMECON is active. The HTHSEC SFR counts
from 0 to 127 before rolling over to increment the SEC time register.
SFR Address:
A2H
Power-On Default: 00H
Bit Addressable:
No
Valid Value:
0 to 127 decimal
SEC—Seconds Time Register
Function:
This register is incremented in 1-second intervals once TCEN in TIMECON is active. The SEC SFR counts from 0 to 59
before rolling over to increment the MIN time register.
SFR Address:
A3H
Power-On Default: 00H
Bit Addressable:
No
Valid Value:
0 to 59 decimal
MIN—Minutes Time Register
Function
This register is incremented in 1-minute intervals once TCEN in TIMECON is active. The MIN SFR counts from 0 to 59
before rolling over to increment the HOUR time register.
SFR Address:
A4H
Power-On Default: 00H
Bit Addressable:
No
Valid Value:
0 to 59 decimal
HOUR—Hours Time Register
Function:
This register is incremented in 1-hour intervals once TCEN in TIMECON is active. The HOUR SFR counts from 0 to 23
before rolling over to 0.
SFR Address:
A5H
Power-On Default: 00H
Bit Addressable:
No
Valid Value:
0 to 23 decimal
To enable the TIC as a real-time clock, the HOUR, MIN, SEC, and HTHSEC registers can be loaded with the current time. Once the
TCEN bit is high, the TIC starts. To use the TIC as a time interval counter, select the count interval—hundredths of seconds, seconds,
minutes, and hours via the ITS0 and ITS1 bits in the TIMECON SFR. Load the count required into the INTVAL SFR.
Note that INTVAL is only an 8-bit register, so user software must take into account any intervals longer than are possible with 8 bits.
Therefore, to count an interval of 20 seconds, use the following procedure:
MOV TIMECON, #0D0H ;Enable 24Hour mode, count seconds, Clear TCEN.
MOV INTVAL, #14H ;Load INTVAL with required count interval...in this case 14H = 20
MOV TIMECON, #0D3H ;Start TIC counting and enable the 8bit INTVAL counter.
Rev. C | Page 72 of 108