UPD77019-013 NEC, UPD77019-013 Datasheet - Page 23

• Manufacturer Part Number: UPD77019-013
• Description: 16 bits/ Fixed-point Digital Signal Processor
• Manufacturer: NEC

2.6 Boot Function
function in host boot mode is same function as other PD7701x family products have.
instruction RAM.
data ROM of the PD77019-013 is masked already and the boot codes cannot be transferred. Other PD7701x
family products store their boot information in 0x4000:Y-0x4004:Y. But the user cannot define these addresses,
because they are in the internal ROM of the PD77019-013.
data width PROM (7 wait accessible) where the boot code should be stored.
There are following cautions on using boot function of the PD77019-013.
The PD77019-013 has self-boot mode and host boot mode.
In host boot mode, the boot code is transferred from host side; external host CPU via host interface. The boot
In self-boot mode, the boot codes are transferred from external data memory or internal data ROM to
The PD77019-013 executes self-boot function transferred from external data memory only. Because internal
Then in the PD77019-013, the following boot information is defined to Y data ROM for self-boot mode.
0x4000:Y
0x4001:Y
0x4002:Y
0x4003:Y
0x4004:Y
To execute boot function in self-boot mode, connect external Y data area with more than the 8K words 16 bits
0
0xC0C0
0
0xC000
0x1000
(Y memory boot/word boot)
(DWTR value is set to 7 wait access mode)
(IWTR value is set to 0 wait access mode)
(sta rt address of boot code stored)
(4K words as program step)
Preliminary Data Sheet
PD77019-013
23