UPD77533 datasheet(48/104 Pages) RENESAS

48 / 104 page

Data Sheet S15671EJ4V0DS

µµµµPD77533

14.1.1 Local commands

In the case of a local command, do not send the next command until a command response is returned. The host

CPU only has a one-packet buffer, and therefore must receive responses from the

µPD77533 without delay.

Do not send local commands to which no response is returned while the

µPD77533 is performing signal

processing.

This is because a little time is required to execute a command received while the

µPD77533 is

performing signal processing, making it impossible to know when command execution is complete.

Figure 14-1. Local Command Flow (with No Hardware Flow Control)

14.1.2 Extension commands

Perform processing for the flow point setting command in the same way as for 14.1.1 Local commands.

For flow point output, because packet transmission/reception can be managed via ACK and NACK, there is no

problem as long as the packet from the

µPD77533 is received without delay in the one-packet buffer provided on the

host CPU side.

Figure 14-2. Flow Point Output Flow (with No Hardware Flow Control)

PD77533

Host CPU

Command transmitted

Response returned

The next command must not be

sent between command transmission

and response return

The host CPU must receive

the response without delay

The next command can be sent now

PD77533

Host CPU

Flow point output returned

ACK returned

The host CPU must receive the packet without delay

Nothing except ACK or NACK can be sent between

flow point output return and ACK return

UPD77533 датащи(PDF) 48 Page - Renesas Technology Corp