408 lines
6.6 KiB
C

/*
* Copyright © 2008 Keith Packard <keithp@keithp.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
#include <stdint.h>
/*
* Validate the SPI-connected EEPROM
*/
sfr at 0x80 P0;
sfr at 0x90 P1;
sfr at 0xA0 P2;
sfr at 0xC6 CLKCON;
sfr at 0xbe SLEEP;
# define SLEEP_USB_EN (1 << 7)
# define SLEEP_XOSC_STB (1 << 6)
sfr at 0xF1 PERCFG;
#define PERCFG_T1CFG_ALT_1 (0 << 6)
#define PERCFG_T1CFG_ALT_2 (1 << 6)
#define PERCFG_T3CFG_ALT_1 (0 << 5)
#define PERCFG_T3CFG_ALT_2 (1 << 5)
#define PERCFG_T4CFG_ALT_1 (0 << 4)
#define PERCFG_T4CFG_ALT_2 (1 << 4)
#define PERCFG_U1CFG_ALT_1 (0 << 1)
#define PERCFG_U1CFG_ALT_2 (1 << 1)
#define PERCFG_U0CFG_ALT_1 (0 << 0)
#define PERCFG_U0CFG_ALT_2 (1 << 0)
sfr at 0xF2 ADCCFG;
sfr at 0xF3 P0SEL;
sfr at 0xF4 P1SEL;
sfr at 0xF5 P2SEL;
sfr at 0xFD P0DIR;
sfr at 0xFE P1DIR;
sfr at 0xFF P2DIR;
sfr at 0x8F P0INP;
sfr at 0xF6 P1INP;
sfr at 0xF7 P2INP;
sfr at 0x89 P0IFG;
sfr at 0x8A P1IFG;
sfr at 0x8B P2IFG;
sbit at 0x90 P1_0;
sbit at 0x91 P1_1;
sbit at 0x92 P1_2;
sbit at 0x93 P1_3;
sbit at 0x94 P1_4;
sbit at 0x95 P1_5;
sbit at 0x96 P1_6;
sbit at 0x97 P1_7;
/*
* UART registers
*/
sfr at 0x86 U0CSR;
sfr at 0xF8 U1CSR;
# define UxCSR_MODE_UART (1 << 7)
# define UxCSR_MODE_SPI (0 << 7)
# define UxCSR_RE (1 << 6)
# define UxCSR_SLAVE (1 << 5)
# define UxCSR_MASTER (0 << 5)
# define UxCSR_FE (1 << 4)
# define UxCSR_ERR (1 << 3)
# define UxCSR_RX_BYTE (1 << 2)
# define UxCSR_TX_BYTE (1 << 1)
# define UxCSR_ACTIVE (1 << 0)
sfr at 0xc4 U0UCR;
sfr at 0xfb U1UCR;
sfr at 0xc5 U0GCR;
sfr at 0xfc U1GCR;
# define UxGCR_CPOL_NEGATIVE (0 << 7)
# define UxGCR_CPOL_POSITIVE (1 << 7)
# define UxGCR_CPHA_FIRST_EDGE (0 << 6)
# define UxGCR_CPHA_SECOND_EDGE (1 << 6)
# define UxGCR_ORDER_LSB (0 << 5)
# define UxGCR_ORDER_MSB (1 << 5)
# define UxGCR_BAUD_E_MASK (0x1f)
# define UxGCR_BAUD_E_SHIFT 0
sfr at 0xc1 U0DBUF;
sfr at 0xf9 U1DBUF;
sfr at 0xc2 U0BAUD;
sfr at 0xfa U1BAUD;
#define MOSI P1_5
#define MISO P1_4
#define SCK P1_3
#define CS P1_2
#define DEBUG P1_1
#define BITBANG 0
#define USART 1
#define nop() _asm nop _endasm;
void
delay (unsigned char n)
{
unsigned char i = 0;
unsigned char j = 0;
while (--n != 0)
while (--i != 0)
while (--j != 0)
nop();
}
#if BITBANG
/*
* This version directly manipulates the GPIOs to synthesize SPI
*/
void
bitbang_cs(uint8_t b)
{
SCK = 0;
CS = b;
delay(1);
}
void
bitbang_out_bit(uint8_t b)
{
MOSI = b;
delay(1);
SCK = 1;
delay(1);
SCK = 0;
}
void
bitbang_out_byte(uint8_t byte)
{
uint8_t s;
for (s = 0; s < 8; s++) {
uint8_t b = (byte & 0x80) ? 1 : 0;
bitbang_out_bit(b);
byte <<= 1;
}
}
uint8_t
bitbang_in_bit(void)
{
uint8_t b;
delay(1);
SCK = 1;
delay(1);
b = MISO;
SCK = 0;
return b;
}
uint8_t
bitbang_in_byte(void)
{
uint8_t byte = 0;
uint8_t s;
uint8_t b;
for (s = 0; s < 8; s++) {
b = bitbang_in_bit();
byte = byte << 1;
byte |= b;
}
return byte;
}
void
bit_bang_init(void)
{
CS = 1;
SCK = 0;
P1DIR = ((1 << 5) |
(0 << 4) |
(1 << 3) |
(1 << 2) |
(1 << 1));
}
#define spi_init() bitbang_init()
#define spi_out_byte(b) bitbang_out_byte(b)
#define spi_in_byte() bitbang_in_byte()
#define spi_cs(b) bitbang_cs(b)
#endif
#if USART
/*
* This version uses the USART in SPI mode
*/
void
usart_init(void)
{
/*
* Configure our chip select line
*/
CS = 1;
P1DIR |= (1 << 2);
/*
* Configure the peripheral pin choices
* for both of the serial ports
*
* Note that telemetrum will use U1CFG_ALT_2
* but that overlaps with SPI ALT_2, so until
* we can test that this works, we'll set this
* to ALT_1
*/
PERCFG = (PERCFG_U1CFG_ALT_1 |
PERCFG_U0CFG_ALT_2);
/*
* Make the SPI pins controlled by the SPI
* hardware
*/
P1SEL |= ((1 << 5) | (1 << 4) | (1 << 3));
/*
* SPI in master mode
*/
U0CSR = (UxCSR_MODE_SPI |
UxCSR_MASTER);
/*
* The cc1111 is limited to a 24/8 MHz SPI clock,
* while the 25LC1024 is limited to 20MHz. So,
* use the 3MHz clock (BAUD_E 17, BAUD_M 0)
*/
U0BAUD = 0;
U0GCR = (UxGCR_CPOL_NEGATIVE |
UxGCR_CPHA_FIRST_EDGE |
UxGCR_ORDER_MSB |
(17 << UxGCR_BAUD_E_SHIFT));
}
void
usart_cs(uint8_t b)
{
CS = b;
}
uint8_t
usart_in_out(uint8_t byte)
{
U0DBUF = byte;
while ((U0CSR & UxCSR_TX_BYTE) == 0)
;
U0CSR &= ~UxCSR_TX_BYTE;
return U0DBUF;
}
void
usart_out_byte(uint8_t byte)
{
(void) usart_in_out(byte);
}
uint8_t
usart_in_byte(void)
{
return usart_in_out(0xff);
}
#define spi_init() usart_init()
#define spi_out_byte(b) usart_out_byte(b)
#define spi_in_byte() usart_in_byte()
#define spi_cs(b) usart_cs(b)
#endif
uint8_t
rdsr(void)
{
uint8_t status;
spi_cs(0);
spi_out_byte(0x05);
status = spi_in_byte();
spi_cs(1);
return status;
}
void
wrsr(uint8_t status)
{
spi_cs(0);
spi_out_byte(0x01);
spi_out_byte(status);
spi_cs(1);
}
void
wren(void)
{
spi_cs(0);
spi_out_byte(0x06);
spi_cs(1);
}
void
write(uint32_t addr, uint8_t *bytes, uint16_t len)
{
wren();
spi_cs(0);
spi_out_byte(0x02);
spi_out_byte(addr >> 16);
spi_out_byte(addr >> 8);
spi_out_byte(addr);
while (len-- > 0)
spi_out_byte(*bytes++);
spi_cs(1);
for (;;) {
uint8_t status = rdsr();
if ((status & (1 << 0)) == 0)
break;
}
}
void
read(uint32_t addr, uint8_t *bytes, uint16_t len)
{
spi_cs(0);
spi_out_byte(0x03);
spi_out_byte(addr >> 16);
spi_out_byte(addr >> 8);
spi_out_byte(addr);
while (len-- > 0)
*bytes++ = spi_in_byte();
spi_cs(1);
}
void
debug_byte(uint8_t byte)
{
uint8_t s;
for (s = 0; s < 8; s++) {
DEBUG = byte & 1;
delay(5);
byte >>= 1;
}
}
#define STRING "\360\252"
#define LENGTH 2
main ()
{
uint8_t status;
uint8_t buf[LENGTH];
int i;
P1DIR |= 2;
CLKCON = 0;
while (!(SLEEP & SLEEP_XOSC_STB))
;
spi_init();
status = rdsr();
/*
* Turn off both block-protect bits
*/
status &= ~((1 << 3) | (1 << 2));
/*
* Turn off write protect enable
*/
status &= ~(1 << 7);
wrsr(status);
write(0x0, STRING, LENGTH);
for (;;) {
read(0x0, buf, LENGTH);
for (i = 0; i < LENGTH; i++)
debug_byte(buf[i]);
}
}