Revision: 1442
Author: [email protected]
Date: Sat Oct 31 23:35:32 2009
Log: updated sd card lib so multiple components can work on the same SPI bus
http://code.google.com/p/jallib/source/detail?r=1442
Modified:
/trunk/include/external/storage/sd_card/sd_card.jal
/trunk/sample/16f877_sd_card.jal
/trunk/sample/18f452_sd_card.jal
=======================================
--- /trunk/include/external/storage/sd_card/sd_card.jal Sun Sep 6 15:42:22
2009
+++ /trunk/include/external/storage/sd_card/sd_card.jal Sat Oct 31 23:35:32
2009
@@ -35,6 +35,10 @@
-- sd_write_pulse -- write 2 bytes of 0's, go 2 bytes forward in
-- current sector
+-- select weather or not to switch SPI modes before every read/write
+-- needed if using more then one component on the SPI bus.
+const byte SD_ALWAYS_SET_SPI_MODE = TRUE
+
-- counters
var byte sd_word_count = 0
var word sd_sector_count = 0
@@ -85,12 +89,12 @@
--------------------------------------------------------------------------------
--- send a command to the sd card (commands with 1 response only
+-- send a command to the sd card (commands with 1 response only)
--------------------------------------------------------------------------------
procedure send_command(byte in command,dword in data, byte out response) is
var byte paramiters[4] at data
var byte x
-
+
-- send a valid CRC byte only for set idle command
-- right bit must always be 1 (stop bit)
if command == SD_GO_IDLE_STATE then
@@ -98,11 +102,11 @@
else
x = 0xFF
end if
-
+
command = command + 64 -- left bits must be 01 (start bits)
spi_master_hw = 0xFF -- send 8 clock pulses
-
+
spi_master_hw = command -- send the command
spi_master_hw = paramiters[3] -- send command parameters
spi_master_hw = paramiters[2] -- send command parameters
@@ -133,17 +137,23 @@
-- initalize the sd card in SPI data transfer mode.
--------------------------------------------------------------------------------
procedure sd_init() is
- var byte reply -- shows if sd card init is ok
-
- -- set sd card to use SPI
- chip_select = high -- chip select high
+ -- put spi into mode 11
+ SSPCON_CKP = 1
+ SSPSTAT_CKE = 0
+
+ var byte reply -- shows if sd card init is ok
+
+ -- steps to set sd card to use SPI
+ sd_chip_select = low -- start chip slect low
+ sd_chip_select = high -- chip select high
for 10 loop
spi_master_hw = 0xFF -- send 0xFF 10 times
end loop
- chip_select = low -- select the sd card (low for rest of program
unless multiple cards)
-
+
+ sd_chip_select = low -- enable the sd card
send_command(SD_GO_IDLE_STATE,0,reply) -- command 0, Resets card to idle
state, get a response
- sd_ready() -- wait till sd card is ready
+ sd_ready() -- wait till sd card is ready
+ sd_chip_select = high -- disable the sd card
end procedure
@@ -151,18 +161,29 @@
-- set the sd card to idle state
--------------------------------------------------------------------------------
procedure sd_set_idle() is
+ sd_chip_select = low -- enable the sd card
+
var byte reply
send_command(SD_STOP_TRANSMISSION,0,reply) -- stop current transmission
sd_ready() -- wait till sd card is ready
send_command(SD_GO_IDLE_STATE,0,reply) -- command 0, Resets card to
idle state
sd_ready() -- wait till sd card is ready
+
+ sd_chip_select = high -- disable the sd card
end procedure
--------------------------------------------------------------------------------
-- tell sd card you will be reading data from a specified sector
--------------------------------------------------------------------------------
procedure sd_start_read(dword in address) is
+ -- put spi into mode 11
+ if SD_ALWAYS_SET_SPI_MODE == TRUE then
+ SSPCON_CKP = 1
+ SSPSTAT_CKE = 0
+ end if
+
var byte reply
+ sd_chip_select = low -- enable the sd card
address = address * 512 -- make sd card sector addressable, sd cards are
normally byte addressable.
send_command(SD_READ_MULTIPLE_BLOCK,address,reply) -- send read multi
block command, ignore reply.
sd_word_count = 0 -- reset count
@@ -175,7 +196,7 @@
--------------------------------------------------------------------------------
procedure sd_read_data(byte out low_byte, byte out high_byte) is
var byte x
-
+
if sd_word_count == 0 then -- beginning of sector read
while spi_master_hw != 0xFE loop -- wait till data is ready to
read
end loop
@@ -183,16 +204,25 @@
low_byte = spi_master_hw -- get data byte
high_byte = spi_master_hw -- get data byte
-
+
if sd_word_count == 255 then -- end of sector read
sd_sector_count = sd_sector_count + 1 -- increment sector number
x = spi_master_hw -- get junk crc data, crc is
disabled
x = spi_master_hw -- get junk crc data, crc is
disabled
end if
-
+
sd_word_count = sd_word_count + 1 -- increment word_count
end procedure
+--------------------------------------------------------------------------------
+-- tell sd card you are finished reading
+-- needed to be the same as other mass media libs
+--------------------------------------------------------------------------------
+procedure sd_stop_read() is
+ sd_set_idle()
+ sd_chip_select = high -- disable the sd card
+end procedure
+
--------------------------------------------------------------------------------
-- send a read pulse to the sd card, go 2 bytes forward in current sector.
--------------------------------------------------------------------------------
@@ -208,6 +238,13 @@
-- must write 1 sector at a time, 512 bytes
--------------------------------------------------------------------------------
procedure sd_start_write(dword in address) is
+ -- put spi into mode 11
+ if SD_ALWAYS_SET_SPI_MODE == TRUE then
+ SSPCON_CKP = 1
+ SSPSTAT_CKE = 0
+ end if
+
+ sd_chip_select = LOW -- enable the sd card
var byte reply
address = address * 512 -- make sd card sector addressable, sd cards are
normally byte addressable.
send_command(SD_WRITE_MULTIPLE_BLOCK,address,reply) -- send read multi
block command, ignore reply.
@@ -248,7 +285,7 @@
x = spi_master_hw
end loop
end if
-
+
sd_word_count = sd_word_count + 1 -- increment word count
end procedure
@@ -259,6 +296,7 @@
procedure sd_stop_write() is
spi_master_hw = 0xFD -- send "stop transmission token"
sd_set_idle()
+ sd_chip_select = high -- disable the sd card
end procedure
--------------------------------------------------------------------------------
@@ -280,10 +318,7 @@
for x loop
sd_write_data(input_byte, input_byte) -- write 2 bytes, 0's as data
end loop
+ sd_chip_select = high -- disable the sd card
end procedure
---------------------------------------------------------------------------------
--- tell sd card you are finished reading
--- needed to be the same as other mass media libs
---------------------------------------------------------------------------------
-ALIAS sd_stop_read is sd_set_idle
+
=======================================
--- /trunk/sample/16f877_sd_card.jal Sun Sep 6 15:41:21 2009
+++ /trunk/sample/16f877_sd_card.jal Sat Oct 31 23:35:32 2009
@@ -24,33 +24,29 @@
pragma target WDT disabled
pragma target LVP disabled
-;const bit enhanced_flash_eeprom = true
-
-include delay -- include the delay library
+-- include the delay library
+include delay
-- setup uart for communication
-;const usart_hw_serial = true -- true = rs232, false = spi
const serial_hw_baudrate = 38400 -- set the baudrate
include serial_hardware
serial_hw_init()
--- pin assignments, choose the pin your led is connected to
-alias led is pin_c0 -- the led pin
-alias led_direction is pin_c0_direction -- the pin's directional
select bit
-
-- setup spi
include spi_master_hw -- includes the spi library
-spi_init(SPI_MODE_11,SPI_RATE_FOSC_16)
-- define spi inputs/outputs
pin_sdi_direction = input -- spi input
pin_sdo_direction = output -- spi output
pin_sck_direction = output -- spi clock
-- spi chip select pin
-ALIAS chip_select_direction is pin_SS_direction
-ALIAS chip_select is pin_SS
-chip_select_direction = output -- chip select/slave select pin
-chip_select = low -- start chip slect low
-
+ALIAS sd_chip_select_direction is pin_SS_direction
+ALIAS sd_chip_select is pin_SS
+sd_chip_select_direction = output -- chip select/slave select pin
+sd_chip_select = high -- disable the sd card
+--
+spi_init(SPI_MODE_11,SPI_RATE_FOSC_16) -- choose spi mode and speed
+
+-- setup sd card library
include sd_card -- include sd card library
sd_init() -- initalize the sd card
=======================================
--- /trunk/sample/18f452_sd_card.jal Sun Sep 6 15:41:33 2009
+++ /trunk/sample/18f452_sd_card.jal Sat Oct 31 23:35:32 2009
@@ -14,9 +14,9 @@
--
-- compiler dependant device definitions
-;include 16f877
+include 16f877
;include 16f877a
-include 18f452
+;include 18f452
pragma target OSC HS -- HS crystal or resonator
pragma target clock 20_000_000 -- oscillator frequency
@@ -24,33 +24,29 @@
pragma target WDT disabled
pragma target LVP disabled
-;const bit enhanced_flash_eeprom = true
-
-include delay -- include the delay library
+-- include the delay library
+include delay
-- setup uart for communication
-;const usart_hw_serial = true -- true = rs232, false = spi
const serial_hw_baudrate = 38400 -- set the baudrate
include serial_hardware
serial_hw_init()
--- pin assignments, choose the pin your led is connected to
-alias led is pin_c0 -- the led pin
-alias led_direction is pin_c0_direction -- the pin's directional
select bit
-
-- setup spi
include spi_master_hw -- includes the spi library
-spi_init(SPI_MODE_11,SPI_RATE_FOSC_16)
-- define spi inputs/outputs
pin_sdi_direction = input -- spi input
pin_sdo_direction = output -- spi output
pin_sck_direction = output -- spi clock
-- spi chip select pin
-ALIAS chip_select_direction is pin_SS_direction
-ALIAS chip_select is pin_SS
-chip_select_direction = output -- chip select/slave select pin
-chip_select = low -- start chip slect low
-
+ALIAS sd_chip_select_direction is pin_SS_direction
+ALIAS sd_chip_select is pin_SS
+sd_chip_select_direction = output -- chip select/slave select pin
+sd_chip_select = high -- disable the sd card
+--
+spi_init(SPI_MODE_11,SPI_RATE_FOSC_16) -- choose spi mode and speed
+
+-- setup sd card library
include sd_card -- include sd card library
sd_init() -- initalize the sd card
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"jallib" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/jallib?hl=en
-~----------~----~----~----~------~----~------~--~---
