From e2b78d20b80d89321d8d9df3ab8ade8407642dfc Mon Sep 17 00:00:00 2001 From: Aleksa Vučković Date: Sun, 2 Jan 2022 22:56:02 +0100 Subject: Adding code --- include/07.pit/pit00.c | 3 +++ include/07.pit/pit01.c | 5 +++++ include/07.pit/pit02.c | 13 +++++++++++++ include/07.pit/pit03.c | 20 ++++++++++++++++++++ 4 files changed, 41 insertions(+) create mode 100644 include/07.pit/pit00.c create mode 100644 include/07.pit/pit01.c create mode 100644 include/07.pit/pit02.c create mode 100644 include/07.pit/pit03.c (limited to 'include/07.pit') diff --git a/include/07.pit/pit00.c b/include/07.pit/pit00.c new file mode 100644 index 0000000..13fd550 --- /dev/null +++ b/include/07.pit/pit00.c @@ -0,0 +1,3 @@ +#include +#include +#include diff --git a/include/07.pit/pit01.c b/include/07.pit/pit01.c new file mode 100644 index 0000000..c199373 --- /dev/null +++ b/include/07.pit/pit01.c @@ -0,0 +1,5 @@ +void add_idt_entry(size_t num,uint32_t offset); +uint32_t tick=0; +const uint32_t TICKS_PER_SECOND=50; +extern uint32_t time; +uint32_t time=0; diff --git a/include/07.pit/pit02.c b/include/07.pit/pit02.c new file mode 100644 index 0000000..523d14b --- /dev/null +++ b/include/07.pit/pit02.c @@ -0,0 +1,13 @@ +void timer_handler() +{ + tick++; + if(tick==TICKS_PER_SECOND) + { + //printf("%d seconds passed\n",time); + tick=0; + time++; + } + + ioport_out(0x20, 0x20); + ioport_out(0xa0,0x20); +} diff --git a/include/07.pit/pit03.c b/include/07.pit/pit03.c new file mode 100644 index 0000000..287adba --- /dev/null +++ b/include/07.pit/pit03.c @@ -0,0 +1,20 @@ +void init_timer(uint32_t frequency) +{ + // Firstly, register our timer callback. + + // The value we send to the PIT is the value to divide it's input clock + // (1193180 Hz) by, to get our required frequency. Important to note is + // that the divisor must be small enough to fit into 16-bits. + uint32_t divisor = 1193180 / frequency; + + // Send the command byte. + ioport_out(0x43, 0x36); + + // Divisor has to be sent byte-wise, so split here into upper/lower bytes. + uint8_t l = (uint8_t)(divisor & 0xFF); + uint8_t h = (uint8_t)( (divisor>>8) & 0xFF ); + + // Send the frequency divisor. + ioport_out(0x40, l); + ioport_out(0x40, h); +} -- cgit v1.2.3