SFSH3.58MCB YAMAR [Yamar Electronics Ltd.], SFSH3.58MCB Datasheet - Page 9

• Manufacturer Part Number: SFSH3.58MCB
• Description: for DC-LIN Asynchronous Communication Over Noisy Lines
• Manufacturer: YAMAR [Yamar Electronics Ltd.]

HDC
HDI
@ 2007 Yamar Electronics Ltd.
In order to read from a control register, the host sends one byte. The byte should be sent more than
200nSec after lowering HDC. The byte begins with the address of the register followed by ”D”H. The
SIG40 will then output the content of the register to pin HDO.
Figure 4.4 shows the pins involved in the reading process:
Note: Writing to Register 1
Writing a change frequencies command to register 1 is not always interpreted correctly by the device.
The device will switch to the correct frequencies pair however, it will not function properly, resulting a
communication lost.
Workaround: When changing frequencies by writing to register 1, use the following procedure:
Lower the H_DC.
Send a command to register 1 containing the require frequencies pair and a false bit rate.
Raise the H_DC
Lower the H_DC
Send a command to register 1 containing the require frequencies pair and the required bit rate.
Raise the H_DC.
For example, when wanting to work with frequencies 3.58MHz and 4.5MHz at 19.2Kbps the correct way
to program the device is described in Figure 4.4.1
Note: Changing only the bit rate can be done with a single write, as described above.
The device operates like a transceiver, therefor while transmitting or writing a command the HDI signal
is looped back to the HDO pin.
HDC:
HDI Read
Command:
4.4
start
bit
T
1
Loopback
Read Command
HDC
HDI
Proprietary and Confidential Information of YAMAR Electronics Ltd.
T
1
0
Address
start bit
1
Figure 4.4 - Reading from a Control register
Figure 4.3 - Writing to a Control Register
2
for 3.58MHz/4.5MHz at
Sending a command
Figure 4.4.1 – Writing to Register
3
Register Address[3:0]
0x15C0
38.4Kbps
stop
bit
Read Command
start
bit
0
9
1
for 3.58MHz/4.5MHz at
Sending a command
2
Configuration Data
0x15F0
19.2Kbps
3
4
0
5
Address
6
1
D(hex)
7
T
3
stop
2
bit
T
3
DS-SIG40 R1.8
3
start
>1/half bit rate
bit
T
stop bit
d
2
Data
a
t
a