3069RF-ZTAT Datasheet, PDF (639/1003 Pages) Renesas Technology Corp – RENESAS 16-BIT SINGLE-CHIP MICROCOMPUTER

(a) Select the on-chip program to be downloaded and the download destination.
When the PPVS bit of FPCS is set to 1, the programming program is selected.
Several programming/erasing programs cannot be selected at one time. If several programs are
set, download is not performed and a download error is returned to the source select error
detect (SS) bit in the DPFR parameter.
Specify the start address of the download destination by FTDAR.
(b) Program H'A5 in FKEY
If H'A5 is not written to FKEY for protection, 1 cannot be written to the SCO bit for download
request.
(c) 1 is written to the SCO bit of FCCS and then download is executed.
To write 1 to the SCO bit, the following conditions must be satisfied.
• RAM emulation mode is canceled.
• H'A5 is written to FKEY.
• The SCO bit writing is executed in the on-chip RAM.
When the SCO bit is set to 1, download is started automatically. When the SCO bit is returned
to the user procedure program, the SCO is cleared to 0. Therefore, the SCO bit cannot be
confirmed to be 1 in the user procedure program.
The download result can be confirmed only by the return value of the DPFR parameter. Before
the SCO bit is set to 1, incorrect judgement must be prevented by setting the DPFR parameter,
that is one byte of the start address of the on-chip RAM area specified by FTDAR, to a value
other than the return value (H'FF).
When download is executed, particular interrupt processing, which is accompanied by the
bank switch as described below, is performed as an internal microcomputer processing. Four
NOP instructions are executed immediately after the instructions that set the SCO bit to 1.
• The user-MAT space is switched to the on-chip program storage area.
• After the selection condition of the download program and the address set in FTDAR
are checked, the transfer processing is executed starting from the on-chip RAM address
specified by FTDAR.
• The SCO bits in FPCS, FECS, and FCCS are cleared to 0.
• The return value is set to the DPFR parameter.
• After the on-chip program storage area is returned to the user-MAT space, the user
procedure program is returned.
The notes on download are as follows.
In the download processing, the values are stored in general registers than CPU.
Rev. 5.0, 09/04, page 617 of 978