在STM32F2XX的reference manual 中
HS USB有4K的fifo ram
这是原文
“It features a dedicated 4-Kbyte data RAM with advanced FIFO management:
– The memory partition can be configured into different FIFOs to allow flexible and
efficient use of RAM
– Each FIFO can contain multiple packets
– Memory allocation is performed dynamically
– The FIFO size can be configured to values that are not powers of 2 to allow the
use of contiguous memory locations”
但是在st提供的STM32_USB-Host-Device_Lib_V2.1.0中
关于fifo 在usb_conf.h中有这样一段说明：
* (vi) In HS case12 FIFO locations should be reserved for internal DMA registers
* so total FIFO size should be 1012 Only instead of 1024
到底这个fifo ram是4KBytes还是1012Bytes?
如果把fifo设置超过1012bytes, 程序运行确实不太稳定。难道是reference manual出错？还是没理解对？ |
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楼主
