EMERSON VE4003S6B1控制器
嵌入式PCI功能VMIVME-7750通過(guò)PCI總線(xiàn)提供非易失性RAM（NVRAM）、計時(shí)器和看門(mén)狗計時(shí)器。嵌入式和實(shí)時(shí)應用程序需要這些功能。這些嵌入式功能的PCI配置空間如下所示?！霸O備ID”字段表示該設備用于VME產(chǎn)品（00），并表示支持的嵌入式功能集?！肮蘄D”和“子系統供應商ID”字段表示VMIC的PICMG分配的供應商ID（114A）?！白酉到yID”字段表示產(chǎn)品的型號（7750）。概述VMIVME-7750提供四個(gè)用戶(hù)可編程定時(shí)器（兩個(gè)16位和兩個(gè)32位），它們完全專(zhuān)用于用戶(hù)應用，不需要任何標準系統功能。每個(gè)定時(shí)器由獨立的發(fā)生器計時(shí)，頻率可選擇為2MHz、1MHz、500kHz和250kHz。每個(gè)定時(shí)器可以獨立啟用，并且每個(gè)定時(shí)器都能夠在超時(shí)時(shí)生成系統中斷。事件可以通過(guò)輪詢(xún)計時(shí)器或啟用計時(shí)器的中斷功能來(lái)計時(shí)。狀態(tài)寄存器允許應用軟件確定哪個(gè)定時(shí)器是任何中斷的原因。
Embedded PCI Functions The VMIVME-7750 provides non-volatile RAM (NVRAM), Timers and a Watchdog Timer via the PCI bus. These functions are required for embedded and real time applications. The PCI configuration space of these embedded functions are shown below.The “Device ID” field indicates that the device is for VME products (00) and indicates the supported embedded feature set. The “Vender ID” and “Subsystem Vendor ID” fields indicate VMIC’s PICMG assigned Vender ID (114A). The “Subsystem ID” field indicates the model number of the product (7750).General The VMIVME-7750 provides four user-programmable timers (two 16-bit and two 32-bit) which are completely dedicated to user applications and are not required for any standard system function. Each timer is clocked by independent generators with selectable rates of 2MHz, 1MHz, 500kHz and 250kHz. Each timer may be independently enabled and each is capable of generating a system interrupt on timeout. Events can be timed by either polling the timers or enabling the interrupt capability of the timer. A status register allows for application software to determine which timer is the cause of any interrupt.
