Note: This module generally requires an external host microcontroller (MCU) to run the upper-layer stack (Profiles) or can be used in "cable replacement" modes depending on the firmware loaded.
Reading or writing the B58944 chip often requires . Using OBD tools requires backing up injector codes separately, as they can be lost during the read/write process. Specific tools recommended for this include Kess, K-TAG, CMD, and BDM100 for BDM access, while MPPS v13/v16 can be used for OBD access but increases the risk of losing injector codes.
: It acts as the "working memory" (SRAM) for the ECU’s microprocessor, storing temporary operational maps and sensor data during vehicle operation. nec b58944 datasheet
: Replacement chips purchased from retailers like Jotrin Electronics or ECUFix are typically "empty" and do not contain pre-programmed data, though as SRAM, they primarily serve as temporary data storage during operation.
What (e.g., oscilloscope, multimeter) you have available. Note: This module generally requires an external host
Based on its identical counterpart, the , the B58944 features the following technical characteristics: Feature Specification Memory Type CMOS Static RAM (SRAM) Capacity 256K-bit (32,768 words x 8 bits) Access Time 70 ns (indicated by the "-70" suffix) Package Type 28-pin Plastic SOP (Small Outline Package) Voltage Range 2.7 V to 5.5 V (B version) Data Retention Low VCC data retention down to 2.0 V Key Features for Automotive Use
If you are purchasing a replacement chip, be aware that many listings for the NEC B58944 describe it as an empty chip Specific tools recommended for this include Kess, K-TAG,
| Parameter | Specification | | :--- | :--- | | | Bluetooth v2.0 + EDR (Enhanced Data Rate) | | Frequency Range | 2.4 GHz ISM Band (2400 – 2483.5 MHz) | | Interface | UART / HCI (Host Controller Interface) | | Modulation | GFSK (Basic Rate), π/4-DQPSK & 8DPSK (EDR) | | Max Data Rate | Up to 3 Mbps (EDR) | | Operating Voltage | 3.3V (Typical) | | Sensitivity | Typically -85 dBm to -90 dBm | | Transmit Power | Class 2 (typical +4 dBm) or Class 1 with external PA support | | Operating Temp | -20°C to +70°C (Standard Commercial) |