3BHE014071P201卡件控制器,ABB產(chǎn)品尺寸
實(shí)時(shí)時(shí)鐘/NVRAM/計(jì)時(shí)器功能MVME2700采用SGS Thomson表面安裝M48T59RAM和時(shí)鐘芯片，提供8KB的非易失性靜態(tài)RAM、實(shí)時(shí)時(shí)鐘和看門(mén)狗定時(shí)器功能。這個(gè)芯片提供時(shí)鐘，振蕩器、晶體、電源故障檢測(cè)、內(nèi)存寫(xiě)保護(hù)、8KBNVRAM和一個(gè)由兩部分組成的包裝中的電池：
? 包含實(shí)時(shí)時(shí)鐘的28針330mil SO設(shè)備振蕩器，電源故障檢測(cè)電路，定時(shí)器邏輯
3BHE014071P201卡件控制器8KB靜態(tài)RAM和電池的鍍金插座? SNAPHAT?電池包含一個(gè)晶體和電池SNAPHAT電池組安裝在M48T559的頂部裝置電池外殼帶有鍵，以防止反向插入。時(shí)鐘提供秒、分、時(shí)、日、日、月和年BCD 24小時(shí)格式。28、29（閏年）和30天的修正月份是自動(dòng)生成的。時(shí)鐘不會(huì)產(chǎn)生中斷。雖然M48T559是一個(gè)8位設(shè)備，但從支持連接至M48T559的ISA總線。參考MVME2600/2700
系列程序員參考指南和M48T559數(shù)據(jù)表詳細(xì)的編程和電池壽命信息。關(guān)于電池實(shí)時(shí)時(shí)鐘的電源是M4T28-BR12 SH1鋰電池電池采用插座，便于拆卸和更換。電池在55°C下的儲(chǔ)存壽命為50年。其使用壽命壽命在很大程度上取決于電路板的環(huán)境溫度和通電占空比。70°C時(shí)，電池的預(yù)期時(shí)間跨度保護(hù)（100%工作周期）為10年。在較低的環(huán)境溫度下，備份時(shí)間相應(yīng)更長(zhǎng)。
如果您打算將電路板放入存儲(chǔ)器，則通過(guò)停止振蕩器將M48T559置于省電模式將延長(zhǎng)電路板的使用壽命電池這在高環(huán)境溫度下尤為重要。進(jìn)入在省電模式下，執(zhí)行PPCBug PS命令。請(qǐng)參閱調(diào)試器第5-4頁(yè)上的命令或其等效的應(yīng)用程序特定命令。將電路板恢復(fù)使用時(shí)，執(zhí)行PPCBug SET命令（設(shè)置mmddyyhhmm）在安裝后重新啟動(dòng)振蕩器并初始化時(shí)鐘。鋰電池包含易燃材料，如鋰和有機(jī)溶劑。如果鋰電池受到虐待或處理不當(dāng)，它們可能爆裂并點(diǎn)燃，可能導(dǎo)致受傷和/或火災(zāi)。在處理鋰電池時(shí)，請(qǐng)仔細(xì)遵循列出的注意事項(xiàng)為了防止事故發(fā)生。
Real-Time Clock/NVRAM/Timer Function
The MVME2700 employs an SGS-Thomson surface-mount M48T59
RAM and clock chip to provide 8KB of nonvolatile static RAM, a realtime clock, and a watchdog timer function. This chip supplies a clock,
oscillator, crystal, power failure detection, memory write protection, 8KB
of NVRAM, and a battery in a package consisting of two parts:
? A 28-pin 330mil SO device containing the real-time clock, the
oscillator, power failure detection circuitry, timer logic, 8KB of
static RAM, and gold-plated sockets for a battery
? A SNAPHAT? battery housing a crystal along with the battery
The SNAPHAT battery package is mounted on top of the M48T559
device. The battery housing is keyed to prevent reverse insertion.
The clock furnishes seconds, minutes, hours, day, date, month, and year in
BCD 24-hour format. Corrections for 28-, 29- (leap year), and 30-day
months are made automatically. The clock generates no interrupts.
Although the M48T559 is an 8-bit device, 8-, 16-, and 32-bit accesses from
the ISA bus to the M48T559 are supported. Refer to the MVME2600/2700
Series Programmer’s Reference Guide and to the M48T559 data sheet for
detailed programming and battery life information.
About the Battery
The power source for the real-time clock is an M4T28-BR12 SH1 lithium
battery which is socketed for easy removal and replacement.
The battery has a storage life of 50 years at 55° C. The length of its service
lifetime is very dependent on the ambient temperature of the board and the
power-on duty cycle. At 70° C, the anticipated time span for battery
protection (100% duty cycle) is 10 years. At lower ambient temperatures,
the backup time is correspondingly longer.
If you intend to place the board in storage, putting the M48T559 in powersave mode by stopping the oscillator will extend the service life of the
battery. This is especially important at high ambient temperatures. To enter
power-save mode, execute the PPCBug PS command. Refer to Debugger
Commands on page 5-4 or its equivalent application-specific command.When restoring the board to service, execute the PPCBug SET command
(set mmddyyhhmm) after installation to restart the oscillator and initialize
the clock.
!
Warning
Lithium batteries incorporate flammable materials such as lithium and
organic solvents. If lithium batteries are mistreated or handled incorrectly,
they may burst open and ignite, possible resulting in injury and/or fire.
When dealing with lithium batteries, carefully follow the precautions listed
below in order to prevent accidents.
