st92f124 STMicroelectronics, st92f124 Datasheet - Page 283

• Manufacturer Part Number: st92f124
• Description: 8/16-bit Single Voltage Flash Mcu Family With Ram, E3 Tmemulated Eeprom, Can 2.0b And J1850 Blpd
• Manufacturer: STMicroelectronics

10.9 J1850 Byte Level Protocol Decoder (JBLPD)
10.9.1 Introduction
The JBLPD is used to exchange data between the
ST9 microcontroller and an external J1850 trans-
ceiver I.C.
The JBLPD transmits a string of variable pulse
width (VPW) symbols to the transceiver. It also re-
ceives VPW encoded symbols from the transceiv-
er, decodes them and places the data in a register.
In-frame responses of type 0, 1, 2 and 3 are sup-
ported and the appropriate normalization bit is
generated automatically. The JBLPD filters out
any incoming messages which it does not care to
receive. It also includes a programmable external
loop delay.
The JBLPD uses two signals to communicate with
the transceiver:
– VPWI (input)
– VPWO (output)
J1850 Byte Level Protocol Decoder (JBLPD)
10.9.2 Main Features
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SAE J1850 compatible
Digital filter
In-Frame Responses of type 0, 1, 2, 3 supported
with automatic normalization bit
Programmable External Loop Delay
Diagnostic 4x time mode
Diagnostic Local Loopback mode
Wide range of MCU internal frequencies
allowed
Low
suspended)
Very low power consumption mode (JBLPD
disabled)
Don’t care message filter
Selectable VPWI input polarity
Selectable Normalization Bit symbol form
6 maskable interrupts
DMA transmission and reception with End Of
Block interrupts
power
consumption
mode
(JBLPD
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