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(GPS on GTA01)
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*Log buffer
 
*Log buffer
  
== GPS on GTA01 ==
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== GTA01上的GPS ==
  
At the GTA01, the host processor is a S3C2410.
+
在GTA01,主要的處理器是S3C2410。
  
=== Hammerhead on the GTA01 ===
+
=== GTA01上的Hammerhead ===
  
 
On the GTA01, the Hammerhead are configured that connected with the host processor through the UART. The UART of data output/input is connected to the UART 1 of the SC2410. The UART of the hardware flow control is connected to the UART 2 of the SC2410.
 
On the GTA01, the Hammerhead are configured that connected with the host processor through the UART. The UART of data output/input is connected to the UART 1 of the SC2410. The UART of the hardware flow control is connected to the UART 2 of the SC2410.

Revision as of 09:38, 28 May 2008

Contents

GPS的內容

GPS (Global Positioning System)是一個衛星定位系統,使用31個衛星。

GPS 類似 "人造衛星" ,以公尺為計算單位。某些形態的GPS,可以較公分為佳的單位進行度量。

利用先進的科技,從IC及其它的元件中接收訊號。

它大量的降低了成本。

因為它大量降低成本的特性,它可以輕鬆的被整合到手機、筆記型電腦及像是耕作用具、瀏覽系統及建築物...等傳統工具中。tion systems and construction equipment.

(你可以在這個位址Global Positioning System Overview取得其它的相關資訊。)

AGPS

這個分類中可以找到所有GPS的資訊.

PMB 2520 Hammerhead

PMB 2520 Hammerhead是GPS的one-chip解決方案,它由全球定位公司的Infineon Technologies所製造。它允許支援A-GPS標準的資料存取。 (相關的資料都可以在 PMB 2520 datasheet中找到) short datasheet

Hammerhead模組

Hammerhead包含了以下的模組:

  • RF front-end with on-chip, high gain and low noise, LNA, I/Q mixers, on-chip polyphase complex IF filter, digitally controlled AGC, and 3-bits ADC for the I and Q paths.
  • Sigma-Delta RF PLL with on-chip PCO and on-chip loop filter.
  • Embedded PLL and NCO for baseband clock generation.
  • Multiple channels digital mixers and parallel correlator engines to enable real time correlation of the PRN code for up to 14 satellites.
  • Post processor including peak detection logic
  • SRAM for storing correlation results

主要界面

Hammerhead整合了三個系列的介面:

  • UART
  • I2C
  • SPI

在Hammerhead的UART是一個full-duplex UART 界面。它被固定在8N1(8 data bits, no parity, 1 stop bit)模式。在GTA01中,主要的處理器透過UART連接到這裡。在Neo1973的所有產品當中,它連接到敘列埠。

主軟體架構

Hammerhead 驅動程式將會以二進位檔的方法載入,它可以像其它的GPS序列埠般,做為 gpsd的介面,輸入如NMEA 資訊。

gps驅動程式目前已可以使用。(之前,它在取得套件二位元檔授權時,有一些問題 [1])

gpsd程式庫提供下列的資訊,做為高階軟體:

  • Position data
  • Library status
  • Time-out and Packet Available

高階軟體傳送下列的訊息到plugin:

  • Assistance data
  • Positioning Commands
  • Configuration Commands

Gpsd 利用以下的部份與系統進行溝通:

  • Communications Drivers
  • System Timer
  • NV storage
  • Log buffer

GTA01上的GPS

在GTA01,主要的處理器是S3C2410。

GTA01上的Hammerhead

On the GTA01, the Hammerhead are configured that connected with the host processor through the UART. The UART of data output/input is connected to the UART 1 of the SC2410. The UART of the hardware flow control is connected to the UART 2 of the SC2410.

Q & A

Q: Can gpsd support Differential GPS.

  • While the neo does not have any means of receiving DGPS or WAAS/SCCM directly, it can be streamed from an internet server.
  • It may be possible to generate a global ionospheric model from stationary (charging?) neos that have GPS signal and cheap internet connections. This would enable very precise positions to be generated
  • This could generate positions accurate to well under a metre, compared to (probably) 2-3m without.
  • The gpsd plugin is the place that these corrections would need to be done, as they need to be performed on a per-satellite basis, before generating the position.
  • This is separate from AGPS - AGPS gives information on current satellite position, or computes your position for you. DGPS is a local minute by minute 'ionospheric weather' for your region.

See also Server:A-GPS.

Q: Can someone upload somewhere an strace of the interaction between gpsd, and the hammerhead chip?

  • Ideally this would be requesting a GPS position every second, starting from 'cold', with no AGPS data, for at least half an hour, in an area where the reciever can see the sky.
  • To aid in reverse engineering efforts.
  • A reverse-engineering page has been created: Hammerhead/Protocol

Q: Can I get NMEA data from the GPS?

A: Not directly. However, the gpsd program 'gpspipe', with the -r switch will output NMEA data with the current position information. The right way to do it is to use libgpsd in your program if possible.

Personal tools

GPS的內容

GPS (Global Positioning System)是一個衛星定位系統,使用31個衛星。

GPS 類似 "人造衛星" ,以公尺為計算單位。某些形態的GPS,可以較公分為佳的單位進行度量。

利用先進的科技,從IC及其它的元件中接收訊號。

它大量的降低了成本。

因為它大量降低成本的特性,它可以輕鬆的被整合到手機、筆記型電腦及像是耕作用具、瀏覽系統及建築物...等傳統工具中。tion systems and construction equipment.

(你可以在這個位址Global Positioning System Overview取得其它的相關資訊。)

AGPS

這個分類中可以找到所有GPS的資訊.

PMB 2520 Hammerhead

PMB 2520 Hammerhead是GPS的one-chip解決方案,它由全球定位公司的Infineon Technologies所製造。它允許支援A-GPS標準的資料存取。 (相關的資料都可以在 PMB 2520 datasheet中找到) short datasheet

Hammerhead模組

Hammerhead包含了以下的模組:

  • RF front-end with on-chip, high gain and low noise, LNA, I/Q mixers, on-chip polyphase complex IF filter, digitally controlled AGC, and 3-bits ADC for the I and Q paths.
  • Sigma-Delta RF PLL with on-chip PCO and on-chip loop filter.
  • Embedded PLL and NCO for baseband clock generation.
  • Multiple channels digital mixers and parallel correlator engines to enable real time correlation of the PRN code for up to 14 satellites.
  • Post processor including peak detection logic
  • SRAM for storing correlation results

主要界面

Hammerhead整合了三個系列的介面:

  • UART
  • I2C
  • SPI

在Hammerhead的UART是一個full-duplex UART 界面。它被固定在8N1(8 data bits, no parity, 1 stop bit)模式。在GTA01中,主要的處理器透過UART連接到這裡。在Neo1973的所有產品當中,它連接到敘列埠。

主軟體架構

Hammerhead 驅動程式將會以二進位檔的方法載入,它可以像其它的GPS序列埠般,做為 gpsd的介面,輸入如NMEA 資訊。

gps驅動程式目前已可以使用。(之前,它在取得套件二位元檔授權時,有一些問題 [1])

gpsd程式庫提供下列的資訊,做為高階軟體:

  • Position data
  • Library status
  • Time-out and Packet Available

高階軟體傳送下列的訊息到plugin:

  • Assistance data
  • Positioning Commands
  • Configuration Commands

Gpsd 利用以下的部份與系統進行溝通:

  • Communications Drivers
  • System Timer
  • NV storage
  • Log buffer

GPS on GTA01

At the GTA01, the host processor is a S3C2410.

Hammerhead on the GTA01

On the GTA01, the Hammerhead are configured that connected with the host processor through the UART. The UART of data output/input is connected to the UART 1 of the SC2410. The UART of the hardware flow control is connected to the UART 2 of the SC2410.

Q & A

Q: Can gpsd support Differential GPS.

  • While the neo does not have any means of receiving DGPS or WAAS/SCCM directly, it can be streamed from an internet server.
  • It may be possible to generate a global ionospheric model from stationary (charging?) neos that have GPS signal and cheap internet connections. This would enable very precise positions to be generated
  • This could generate positions accurate to well under a metre, compared to (probably) 2-3m without.
  • The gpsd plugin is the place that these corrections would need to be done, as they need to be performed on a per-satellite basis, before generating the position.
  • This is separate from AGPS - AGPS gives information on current satellite position, or computes your position for you. DGPS is a local minute by minute 'ionospheric weather' for your region.

See also Server:A-GPS.

Q: Can someone upload somewhere an strace of the interaction between gpsd, and the hammerhead chip?

  • Ideally this would be requesting a GPS position every second, starting from 'cold', with no AGPS data, for at least half an hour, in an area where the reciever can see the sky.
  • To aid in reverse engineering efforts.
  • A reverse-engineering page has been created: Hammerhead/Protocol

Q: Can I get NMEA data from the GPS?

A: Not directly. However, the gpsd program 'gpspipe', with the -r switch will output NMEA data with the current position information. The right way to do it is to use libgpsd in your program if possible.