CD00001237 datasheet(52/105 Pages) STMICROELECTRONICS

52 / 105 page

ST6215C ST6225C

52/105

8-BIT TIMER (Cont’d)

9.2.7 Register Description

PRESCALER COUNTER REGISTER (PSCR)

Address: 0D2h - Read/Write

Reset Value: 0111 1111 (7Fh)

Bit 7 = PSCR7: Not used, always read as “0”.

Bits 6:0 = PSCR[6:0] Prescaler LSB.

TIMER COUNTER REGISTER (TCR)

Address: 0D3h - Read / Write

Reset Value: 1111 1111 (FFh)

Bits 7:0 = TCR[7:0] Timer counter bits.

TIMER STATUS CONTROL REGISTER (TSCR)

Address: 0D4h - Read/Write

Reset Value: 0000 0000 (00h)

Bit 7 = TMZ Timer Zero bit.

A low-to-high transition indicates that the timer

count register has underflowed. It means that the

TCR value has changed from 00h to FFh.

This bit must be cleared by user software.

0: Counter has not underflowed

1: Counter underflow occurred

Bit 6 = ETI Enable Timer Interrupt.

When set, enables the timer interrupt request. If

ETI=0 the timer interrupt is disabled. If ETI=1 and

TMZ=1 an interrupt request is generated.

0: Interrupt disabled (reset state)

1: Interrupt enabled

Bit 5 = TOUT Timer Output Control.

When low, this bit selects the input mode for the

TIMER pin. When high the output mode is select-

ed.

0: Input mode (reset state)

1: Output mode, the TIMER pin is configured as

push-pull output

Bit 4 = DOUT Data Output.

Data sent to the timer output when TMZ is set high

(output mode only). Input mode selection (input

mode only).

Bit 3 = PSI: Prescaler Initialize bit.

Used to initialize the prescaler and inhibit its count-

ing. When PSI=“0” the prescaler is set to 7Fh and

the counter is inhibited. When PSI=“1” the prescal-

er is enabled to count downwards. As long as

PSE=“1” both counter and prescaler are not run-

ning

0: Counting disabled

1: Counting enabled

Bits 1:0 = PS[2:0] Prescaler Mux. Select.

These bits select the division ratio of the prescaler

Table 13. Prescaler Division Factors

Table 14. 8-Bit Timer Register Map and Reset Values

PSCR

TCR7

TCR6

TCR5

TCR4

TCR3

TCR2

TCR1

TCR0

TMZ

ETI

TOUT DOUT

PSI

PS2

PS1

PS0

PS2

PS1

PS0

Divided by

128

Address

(Hex.)

7654

3210

0D2h

PSCR

Reset Value

PSCR7

PSCR6

PSCR5

PSCR4

PSCR3

PSCR2

PSCR1

PSCR0

0D3h

TCR

Reset Value

TCR7

TCR6

TCR5

TCR4

TCR3

TCR2

TCR1

TCR0

0D4h

TSCR

Reset Value

TMZ

ETI

TOUT

DOUT

PSI

PS2

PS1

PS0

CD00001237 数据表(PDF) 52 Page - STMicroelectronics

CD00001237 数据表(HTML) 52 Page - STMicroelectronics

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

数据表下载

链接网址

CD00001237 数据表(PDF) 52 Page - STMicroelectronics

CD00001237 数据表(HTML) 52 Page - STMicroelectronics

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

数据表 下载

链接网址

数据表下载