STPC4EDBC datasheet(28/93 Pages) STMICROELECTRONICS

28 / 93 page

STRAP OPTIONS

28/93

Release 1.5 - January 29, 2002

3.1. POWER-ON STRAP REGISTER DESCRIPTIONS

3.1.1. ADPC STRAP REGISTER 0 CONFIGURATION

Strap0

Access = 0022h/0023h

Regoffset = 04Ah

76543210

MD[7]

MD[6]

See Table

below

MD[4]

Rsv

See Table

below

See Table

below

See Table

belowl

This register defaults to the values sampled on MD[7:4] pins after reset

Bit Number Sampled

Mnemonic

Description

Bits 7-6

MD[7:6]

PCICLK PLL set-up:

The value sampled on MD[7:6] controls the

PCICLK PLL programming according to PCICLK frequency.

MD7 MD6

PCICLK frequency between 16 & 32 MHz

PCICLK frequency between 32 & 64 MHz

Reserved

Bit 5

MD[5]

For the parts referenced STPCC4, see section Section 3.1.1.bit 2.

MD[44]

For the parts referenced STPCC5, this s

trap selects betwen Local

Bus or ISA mode.

0 = ISA Mode

1 = Local Bus Mode

This strap is not readable in a register for the STPCC4.

Bit 4

MD[4]

PCICLK division: This bit reflects the value sampled on [MD4] and is

used together with MD[17] to select the PCICLK frequency.

MD4 MD17

PCI Clock output = HCLK / 4

PCI Clock output = HCLK / 3

PCI Clock output = HCLK / 2

Bits 2

Rsv

For the parts referenced STPCC4 These bits are reserved

MD[5]

Host Memory synchronization. This bit reflects the value sampled on

MD[5] and controls the MCLK/HCLK synchronization.

0: MCLK and HCLK not synchronized

1: MCLK and HCLK synchronized for improved system performance.

Bit 1-0

Rsv

For the parts referenced STPCC4 These bits are reserved

MD[4,17]

For the parts referenced STPCC5.

These bits reflect the values sampled on MD[17] pin and

controls the PCI clock output in conjunction with MD[4], as

follows:

MD4 MD17

PCI Clock output = HCLK / 4

PCI Clock output = HCLK / 3

PCI Clock output = HCLK / 2

STPC4EDBC 数据表(PDF) 28 Page - STMicroelectronics

STPC4EDBC 数据表(HTML) 28 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

数据表下载

链接网址

STPC4EDBC 数据表(PDF) 28 Page - STMicroelectronics

STPC4EDBC 数据表(HTML) 28 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

数据表 下载

链接网址

数据表下载