SM8213AM datasheet(15/33 Pages) NPC

15 / 33 page

SM8213AM

NIPPON PRECISION CIRCUITS—15

Address/Parameter Data Transmission (CPU to SM8213AM)

After device reset initialization, the address and

parameter data is transmitted from the CPU in 32-bit

batches, 1 parameter batch and 8 address batches for

a total of 9 batches (288 bits), on SDI in sync with

the falling edge of the SCK clock (see “Power-ON

Mode” section).

The SM8213AM supports 8 independent addresses

(7 normal addresses: A, B, C, D, E, F, G and H + 1

dummy address: H). Also, each address can be

assigned a frame number to cover all kinds of group

calls or subsidiary services.

Any of the 8 addresses can be individually disabled

using the “ADDRESS ENABLE” ﬂag when setting

the addresses.

Conversely, is less than 7 addresses are used, then

the use of address H is restricted and as a result the

device can be used as a normal decoder.

The address data for each of the 8 addresses com-

prises an 18-bit address plus two function bits used

to select one of four sub-addresses. Then, one MSB

bit (0 for address signals), ten BCH(31,21) format

generated check bits and an even-parity bit are added

to form 32-bit code word representing the address

information which is then stored in RAM. This

address information is then compared with the

received data to determine correct addressing.

Ensure that there are not multiple writes requests to

turn ON the same address.

Even if the number of addresses used is less than 8,

all addresses should be set immediately after power

is applied and immediately after reset. If not all

addresses are set, subsequent operation may become

unstable.

Each address is 18 bits long and should be input

MSB ﬁrst. Refer to the “AC Characteristics” section

for

SCK

and

data

speciﬁcations,

and

the

“Data/Flags” section for data and ﬂag functions.

When setting parameters and addresses in write

mode, the SCK clock frequency should not be less

than 1200 Hz. If this occurs, the SCK counter is rein-

itialized. This function, however, does make restor-

ing operation easy even if this or another clock is

accidentally input.

Figure 8. Address/parameter transmit timing

BUSY

ATTN

SCK

SDI

SDO

BUSY

WRITE MODE

PREAMBLE MODE

8-bit unit time data

8-bit unit time clock

8-bit unit time indeterminate data

DA T

READ

READY

START

WRITE

READ

DA T

32-bit unit time parameter/address data

max

28.4ms

Refer to the AC Characteristics section for detailed timing specifications.

2bit time max

1.67ms max

129ms max

SM8213AM Datasheet(PDF) 15 Page - Nippon Precision Circuits Inc

SM8213AM Datasheet(HTML) 15 Page - Nippon Precision Circuits Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

Datasheet Download

Link URL