Cypress Semiconductor Perform CY7C1372D Guia do Utilizador descarregar pdf (Página 95)

8 Generic Components

8.1 ii_event_log

Supported Platforms: Quixote

Description:

The event log component is to provide a mechanism for recording the chronology of important

system events. Using alerts, the application can know when triggers occurred, how much data

was collected/played, be alerted when data is out-of-range or a data flow error occurred, and mark

the data stream for other reasons. This provides a precision timed log of all of the important

events that occurred. For each event input, the logic creates an alert message that records the

time of the event, the type of event, and other information that is inserted into a FIFO.

There are 32 event input triggers to the ii_event_log component that may be used to trigger the

alert message creation. Event trigger logic looks for rising edges on the input event_in signals by

sampling the inputs with the system clock (clk). The application logic can also write in a user

event that is timestamped and recorded in the FIFO.

The 32-bit time stamp is driven by a reference clock that is usually a known frequency or sample

period clock. It can be enabled to run by the logic independently of other devices to provide a

system time.

Word 31 30..28 26..16 15..8 7..0

0 Alert

Class

Alert

type

0 Error Channel 0x00

1 Time stamp

2 Event Marker or User Data

Table 21: ii_event_log Alert Message Format

The alert class just reports whether the input event was on event input 15 to 0 (reports 1 as class)

or 31 to 16 (reports 0 as class). This can be used to divide alert message types into A/D and D/A

for example. The error channel is either the ad_error_channel input when for event inputs 15 to 0,

or dac_error_channel input for event inputs 31 to 16.

The time stamp records the system time when the alert was created. Since multiple alerts can

occur simultaneously, they are serviced in order of occurrence. The event log logic is normally

clocked at a much higher rate than the time stamp, so the alert messages have a proper time

stamp recorded. The event log logic requires 6 clock cycles to create a message.

The event marker or user data word allows the logic to append any important information to the

alert message. This is input on the event_marker input for all events other than the user event.

For user events, this is input on the data bus.

Innovative Integration FrameWork Logic User Guide 95

1 2 ... 90 91 92 93 94 95 96 97

Sem comentários

Cypress Semiconductor Perform CY7C1372D Guia do Utilizador Página 95