Memory Usage Monitor¶

Authors: Aarón Cuevas López
IO: Frame Source, Register Access
ONIX ID: 28
ONIX Hubs: PCIe Host

Description¶

The Memory Usage Monitor produces periodic samples that contain information about data buffer memory status. This device is useful for monitoring if frames are being cleared fast enough by the host PC to prevent real-time delays or overflows. Ideally, buffering should never be used and the memory usage should remain at 0.

Register Programming¶

Address	Name	Access	Time of Effect	POR Value	Reset Action	Description
0x00	ENABLE	R/W	On Reset	Implementation dependent, see hub documentation	None	The LSB is used to enable or disable the device data stream: 0x0: data output disabled 0x1: data output enabled
0x01	CLK_DIV	R/W	On Reset	CLK_HZ / HB_HZ where HB_HZ is a implementation dependent default rate	None	Read frequency clock divider ratio. Minimum value is CLK_HZ / 10e6
0x02	CLK_HZ	R	N/A	N/A	None	The frequency parameter, CLK_HZ, used in the calculation of CLK_DIV.
0x03	MEM_WORDS	R	N/A	N/A	None	The total number of 32-bit words in memory.

Device To Host Data Frames¶

Each frame transmitted to the host is structured as follows:

Host To Device Data Frames¶

This device does not accept input frames. All write attempts will fail with an error.

Load Test Device

FMC Host Analog IO Device