IBM PPC750FX User Manual - page 80
Evaluation Board Manual
PPC750FX Evaluation Board
Preliminary
CPLD Programming
Page 80 of 115
750FXebm_ch11.fm
June 10, 2003
11.1.2.4 decode_block Program
The following code listing defines the function of the logic in the
decode_block
part of the CPLD:
INCLUDE "lpm_ff.inc"; -- 10:30 AM Mar 26, 2003
INCLUDE "lpm_counter.inc";
SUBDESIGN decode_block
(
sysreset_n
: INPUT;
sysclk
: INPUT;
CSTiming_n
: INPUT;
LBootCS_n
: INPUT; -- 16 Bit flash/sram or 32 bit FLASH (32MB) chip select
lcs_n[3..0]
: INPUT; -- latched from upper address/data bus
ldev_addr[21..19] : INPUT; -- latched device address. Note that this is not the PowerPC conventional
-- address ordering. Device Addr0 is the LSB.
flash_n/sram_sel : INPUT;
bootsmall_n
: INPUT;
ldevR_W_n
: INPUT;
Dev_We_n0
: INPUT;
nvram_burst_cs_n: INPUT;
small_flash_lo_cs_n: OUTPUT; -- default lboot_cs_n, swappable to lcs_n[0]
small_flash_hi_cs_n: OUTPUT; -- default lboot_cs_n, swappable to lcs_n[0]
sram_lo_cs_n
: OUTPUT; -- default lboot_cs_n, swappable to lcs_n[0]
sram_hi_cs_n
: OUTPUT; -- default lboot_cs_n, swappable to lcs_n[0]
big_flash_cs_n
: OUTPUT; -- default lcs_n[0], swappable to lboot_cs_n
Read_n
: OUTPUT;
Write_n
: OUTPUT;
uart_cs_n
: OUTPUT; -- lcs_n[2]
nvram_cs_n
: OUTPUT; -- lcs_n[3]
test
: OUTPUT; -- test only
fpga_cs_n
: OUTPUT; -- lcs_n[1]
)
VARIABLE
abovebootarea
: NODE; -- memory above boot area
bootarea
: NODE; -- 750FX boots from this area
lowerarea
: NODE;
upperarea
: NODE;
hiarea
: NODE;
loarea
: NODE;
toparea
: NODE;
botarea
: NODE;
SRAM/FLASH/BIG : NODE; -- boot from small flash