R5F524TAADFP is the 256 KB, 16 KB RAM member of the RX24T group in the 100-pin package, and it carries silicon revision A rather than B. That last detail is the one that catches people out. The two revisions are pin compatible, program compatible in almost every respect, and documented in the same manual with a correction table at the front – but the errata differ, and a firmware image pulled from an A-revision part may depend on behaviour that the B revision fixed.
What Revision A Means For A Read
Nothing changes about the read itself: code is at FFFC0000h to FFFFFFFFh, the E2 data flash is a separate eight kilobytes, and the option bytes sit in the OFS window. What changes is the interpretation. When the extracted image is used to build a replacement, the build should target the revision that is actually available, and the differences should be checked against the errata list rather than assumed away.
Sixteen Kilobytes Of RAM Is A Constraint
The 32 KB variant of the same 256 KB array exists. This one has sixteen, which means the application was written with a hard ceiling: a single control loop, one motor, no dynamic allocation, and communication handled in a fixed buffer. If a rebuild is planned on a larger part, the loop timing will change because RAM access and stack placement change, and a drive that was stable can become marginal.
The Read Plan
| Region | Address | Note |
|---|---|---|
| ROM | FFFC0000h to FFFFFFFFh | 2 KB blocks |
| E2 data flash | separate 8 KB | 2 KB erase blocks |
| Option bytes | OFS0 / OFS1 | watchdog, LVD, clock |
| ID code | FFFFFFA0h | control byte + 15 ID bytes |
Each area is acquired with its own pass and verified independently. The ROM is read block by block so a failed block can be re-read without repeating the whole array.
Protection And What It Blocks
ID code protection gates boot-mode SCI and the debugging emulator. ROM code protection, a 32-bit value in block 0, disables reading and rewriting through a parallel programmer when it is zero, and reading only when it is one. Start-up program protection pairs blocks 0 to 7 with 8 to 15 so a bootloader can rewrite the start-up code in place. Area protection restricts self-programming to selected blocks. Every one of these is a control, not a destructive act; the array survives a read untouched.
Motor-Specific Capture
On a 100-pin RX24T the pin count exists to bring out three-phase PWM, encoder inputs, and the analog feedback for two motors. If the unit still runs, we capture the MTU3 channel assignment, the GPT configuration, the comparator and POE settings, and the ADC trigger source. That record is what turns a hex file into a drive that can be re-qualified instead of one that merely spins a motor.
Handover
Intel HEX, E2 binary, option bytes, block map, ID code page, and – where captured – the peripheral configuration record. The report states the silicon revision read from the part and whether the FPU was enabled.
Revision In The Report
Silicon revision is one line in the report and it prevents a recurring argument. When a replacement built from a recovered image behaves slightly differently from the original, the first question is whether both parts are the same revision.
Recording the revision at intake means that question is answered before it is asked, and it also tells the buyer what to order – A and B revisions are both still in circulation in distribution stock.
Intake Notes
Say how many motors the board drives and what the DC bus is. Note whether the heatsink is bonded or screwed, because that decides how the board is handled. The services page lists what to include; the contact form is faster for a scope question. The 32 KB RAM variant is R5F524TBADFP, and the 64-pin family member is R5F524TAADFM.