DSP56857 datasheet(377/662 Pages) FREESCALE

377 / 662 page

Quad Timer (TMR), Rev. 4

Freescale Semiconductor

13-11

13.9 Register Descriptions (TMR_BASE = $1FFE80)

13.9.1 Timer Control Registers (CTL)

There are four Timer Control Registers in this occurrence. Their addresses are:

TMRA0_CTRL (Timer A, Channel 0 Control)—Address: TMRA_BASE + $6

TMRA1_CTRL (Timer A, Channel 1 Control)—Address: TMRA_BASE + $E

TMRA2_CTRL (Timer A, Channel 2 Control)—Address: TMRA_BASE + $16

TMRA3_CTRL (Timer A, Channel 3 Control)—Address: TMRA_BASE + $1E

Figure 13-4. TMR Control Register (CTL)

See Programmer’s Sheet on Appendix page B - 90

13.9.1.1 Count Mode (CM)—Bits 15–13

These bits control the basic counting behavior of the counter.

•

000 = No operation

•

001 = Count rising edges of primary source

•

010 = Count rising and falling edges of primary source

•

011 = Count rising edges of primary source while secondary input high active1

•

100 = Quadrature count mode, uses primary and secondary sources

•

101 = Count rising edges of primary source; secondary source specifies direction

(1 = minus)

•

110 = Edge of secondary source triggers primary count until compare

•

111 = Cascaded Counter mode (up/down)2

13.9.1.2 Primary Count Source (PCS)—Bits 12–9

These bits select the primary count source.

•

0000 = Counter 0 input pin (TIO0)

•

0001 = Counter 1 input pin (TIO1)

•

0010 = Counter 2 input pin (TIO2)

Base + $6, $E,

$16, $1E

Read

PCS

SCS

ONCE LENGTH

DIR

EXT

INIT

OM (OFLAG)

Write

Reset

000

1. Rising edges counted only when IPS = 0. Falling edges counted when IPS = 1.

2. Primary count source must be set to one of the counter outputs.

DSP56857 Datasheet(PDF) 377 Page - Freescale Semiconductor, Inc

DSP56857 Datasheet(HTML) 377 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