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Timer 1 control register 2 (t1c2), Watchdog control register (wdc), Atar862-8 – Rainbow Electronics ATAR862-8 User Manual

Page 43

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43

ATAR862-8

4589B–4BMCU–02/03

Timer 1 Control Register 2
(T1C2)

Address: "7"hex - Subaddress: "9"hex

* Bit 3 -> MSB, Bit 0 -> LSB

Watchdog Control Register
(WDC)

Address: "7"hex - Subaddress: "A"hex

* Bit 3 -> MSB, Bit 0 -> LSB

Both these bits control the time interval for the watchdog reset.

Bit 3 *

Bit 2

Bit 1

Bit 0

T1BP

T1CS

T1IM

Reset value: x111b

T1BP

T

imer

1

SUBCL

B

y

P

assed

T1BP = 1, TIOUT = T1MUX
T1BP = 0, T1OUT = SUBCL

T1CS

T

imer

1

input

C

lock

S

elect

T1CS = 1, CL1 = SUBCL (see Figure 27)
T1CS = 0, CL1 = SYSCL (see Figure 27)

T1IM

T

imer

1 I

nterrupt

M

ask

T1IM = 1, disables Timer 1 interrupt
T1IM = 0, enables Timer 1 interrupt

Bit 3 *

Bit 2

Bit 1

Bit 0

WDL

WDR

WDT1

WDT0

Reset value: 1111b

WDL

W

atch

D

og

L

ock mode

WDL = 1, the watchdog can be enabled and disabled by using the WDR-bit
WDL = 0, the watchdog is enabled and locked. In this mode the WDR-bit has no

effect. After the WDL-bit is cleared, the watchdog is active until a
system reset or power-on reset occurs.

WDR

W

atch

D

og

R

un and stop mode

WDR = 1, the watchdog is stopped/disabled
WDR = 0, the watchdog is active/enabled

WDT1

W

atch

D

og

T

ime

1

WDT0

W

atch

D

og

T

ime

0

WDT1

WDT0

Divider

Delay Time to Reset with

SUBCL = 32 kHz

Delay Time to Reset with

SYSCL = 2/1 MHz

0

0

512

15.625 ms

0.256 ms/0.512 ms

0

1

2048

62.5 ms

1.024 ms/2.048 ms

1

0

16384

0.5 s

8.2 ms/16.4 ms

1

1

131072

4 s

65.5 ms/131 ms