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/*****************************************************************************/
/*
$Id$
M68302 SCC Polled Driver
*/
/*****************************************************************************/
#include <bsp.h>
#include <rtems/m68k/m68302.h>
#include <m68302scc.h>
#define M68302_SCC_COUNT (3)
static volatile m302_SCC_t *scc[M68302_SCC_COUNT] = { 0, 0, 0 };
static volatile m302_SCC_Registers_t *scc_reg[M68302_SCC_COUNT] = { 0, 0, 0 };
static int scc_translate[M68302_SCC_COUNT] = { 0, 0, 0 };
static const uint16_t baud_clocks[] =
{
(SYSTEM_CLOCK / ( 4800 * 16)),
(SYSTEM_CLOCK / ( 9600 * 16)),
(SYSTEM_CLOCK / ( 19200 * 16)),
(SYSTEM_CLOCK / ( 38400 * 16)),
(SYSTEM_CLOCK / ( 57600 * 16)),
(SYSTEM_CLOCK / (115700 * 16))
};
void scc_initialise(int channel, int baud, int translate)
{
uint16_t scon;
if (channel < M68302_SCC_COUNT)
{
scc[channel] = &m302.scc1 + channel;
scc_reg[channel] = &m302.reg.scc[channel];
scc_translate[channel] = translate;
scon = (baud_clocks[baud] & 0xF800) == 0 ? 0 : 1;
scon |= (((baud_clocks[baud] / (1 + scon * 3)) - 1) << 1) & 0x0FFE;
scc_reg[channel]->scon = scon;
scc_reg[channel]->scm = 0x0171;
scc[channel]->bd.tx[0].status = 0x2000;
scc[channel]->bd.tx[0].length = 0;
scc[channel]->bd.tx[0].buffer =
(uint8_t*) &(scc[channel]->bd.tx[1].buffer);
scc[channel]->bd.rx[0].status = 0x2000;
scc[channel]->bd.rx[0].length = 0;
scc[channel]->bd.rx[0].buffer =
(uint8_t*) &(scc[channel]->bd.rx[1].buffer);
scc[channel]->parm.rfcr = 0x50;
scc[channel]->parm.tfcr = 0x50;
scc[channel]->parm.mrblr = 0x0001;
scc[channel]->prot.uart.max_idl = 0x0004;
scc[channel]->prot.uart.brkcr = 1;
scc[channel]->prot.uart.parec = 0;
scc[channel]->prot.uart.frmec = 0;
scc[channel]->prot.uart.nosec = 0;
scc[channel]->prot.uart.brkec = 0;
scc[channel]->prot.uart.uaddr1 = 0;
scc[channel]->prot.uart.uaddr2 = 0;
scc[channel]->prot.uart.character[0] = 0x0003;
scc[channel]->prot.uart.character[1] = 0x8000;
scc_reg[channel]->scce = 0xFF;
scc_reg[channel]->sccm = 0x15;
scc_reg[channel]->scm = 0x17d;
}
}
unsigned char scc_status(int channel, unsigned char status)
{
uint16_t rx_status;
m302.reg.wcn = 0;
if ((channel < M68302_SCC_COUNT) && scc[channel])
{
rx_status = scc[channel]->bd.rx[0].status;
if ((rx_status & 0x8000) == 0)
{
if (rx_status & 0x003B)
{
return 2;
}
if (status == 0)
{
return 1;
}
}
}
return 0;
}
unsigned char scc_in(int channel)
{
m302.reg.wcn = 0;
if ((channel < M68302_SCC_COUNT) && scc[channel])
{
if ((scc[channel]->bd.rx[0].status & 0x8000) == 0)
{
unsigned char c;
c = *(scc[channel]->bd.rx[0].buffer);
scc[channel]->bd.rx[0].status = 0xa000;
return c;
}
}
return 0;
}
void scc_out(int channel, unsigned char character)
{
if ((channel < M68302_SCC_COUNT) && scc[channel])
{
do
{
m302.reg.wcn = 0;
}
while (scc[channel]->bd.tx[0].status & 0x8000);
*(scc[channel]->bd.tx[0].buffer) = character;
scc[channel]->bd.tx[0].length = 1;
scc[channel]->bd.tx[0].status = 0xa000;
if (scc_translate[channel])
{
if (character == '\n')
{
scc_out(channel, '\r');
}
}
}
}
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