Flash Memory Register Descriptions; Flash Memory Control Register 1 (Flmcr1) - Renesas Hitachi H8S/2194 Series Hardware Manual

7.3

Flash Memory Register Descriptions

7.3.1

Flash Memory Control Register 1 (FLMCR1)

Bit : 7
FWE
— *
Initial value :
R/W : R
Note: * Determined by the state of the FWE pin.
FLMCR1 is an 8-bit register used for flash memory operating mode control. Program-verify
mode or erase-verify mode is entered by setting SWE to 1 when FWE = 1. Program mode is
entered by setting SWE to 1 when FWE = 1, then setting the PSU bit in FLMCR2, and finally
setting the P bit. Erase mode is entered by setting SWE to 1 when FWE = 1, then setting the
ESU bit in FLMCR2, and finally setting the E bit. FLMCR1 is initialized by a reset, in power-
down state (excluding the medium-speed mode, module stop mode, and sleep mode), or when a
low level is input to the FWE pin. Its initial value is H'80 when a high level is input to the FWE
pin, and H'00 when a low level is input. When on-chip flash memory is disabled, a read will
return H'00, and writes are invalid.
Writes to the SWE bit in FLMCR1 are enabled only when FWE = 1; writes to the EV and PV
bits only when FWE=1 and SWE=1; writes to the E bit only when FWE = 1, SWE = 1, and ESU
= 1; and writes to the P bit only when FWE = 1, SWE = 1, and PSU = 1.
Bit 7: Flash Write Enable (FWE)
Sets hardware protection against flash memory programming/erasing.
Bit 7
FWE Description
0 When a low level is input to the FWE pin (hardware-protected state)
1 When a high level is input to the FWE pin
6 5
SWE —
0 0
R/W —
4 3 2
— EV PV
0 0 0
— R/W R/W
Rev. 2.0, 11/00, page 131 of 1037
1 0
E P
0 0
R/W R/W