SPMC68CK338CPV14 datasheet(23/133 Pages) FREESCALE

23 / 133 page

MC68CK338

MOTOROLA

MC68CK338TS/D

SWP — Software Watchdog Prescaler

This bit controls the value of the software watchdog prescaler.

0 = Software watchdog clock not prescaled

1 = Software watchdog clock prescaled by 512

SWT[1:0] — Software Watchdog Timing

This field selects the divide ratio used to establish software watchdog time-out period. Table 9 gives the

ratio for each combination of SWP and SWT bits.

HME — Halt Monitor Enable

0 = Disable halt monitor function

1 = Enable halt monitor function

BME — Bus Monitor Enable

0 = Disable bus monitor function for internal to external bus cycles.

1 = Enable bus monitor function for internal to external bus cycles.

BMT[1:0] — Bus Monitor Timing

This bit field selects the time-out period in system clocks for the bus monitor. Refer to Table 10.

3.4.2 Bus Monitor

The internal bus monitor checks for excessively long DSACK response times during normal bus cycles

and for excessively long DSACK or AVEC response times during interrupt acknowledge (IACK) cycles.

The monitor asserts BERR if the response time exceeds a user-specified time-out period.

DSACK and AVEC response times are measured in clock cycles. The maximum allowable response

time can be selected by setting the BMT[1:0] field.

Table 9 Software Watchdog Timing Field

SWP

SWT[1:0]

Watchdog Time-Out Period

000

÷ f

sys

001

211

÷ f

sys

010

213

÷ f

sys

011

215

÷ f

sys

100

218

÷ f

sys

101

220

÷ f

sys

110

222

÷ f

sys

111

224

÷ f

sys

Table 10 Bus Monitor Time-Out Period

BMT[1:0]

Bus Monitor Time-Out Period

64 system clocks

32 system clocks

16 system clocks

8 system clocks

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

SPMC68CK338CPV14 Datasheet(PDF) 23 Page - Freescale Semiconductor, Inc

SPMC68CK338CPV14 Datasheet(HTML) 23 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL