Increase CLKDIV for IOW because 5170 doesn't have valid data for 30ns

polpo · Jan 15, 2024 · 9128a40 · 9128a40
1 parent 6021416
commit 9128a40
Show file tree

Hide file tree

Showing 2 changed files with 4 additions and 2 deletions.
diff --git a/sw/isa_io.pio b/sw/isa_io.pio
@@ -26,13 +26,14 @@ read_addr:
 .wrap
 
 % c-sdk {
-static inline void iow_program_init(PIO pio, uint sm, uint offset) {
+static inline void iow_program_init(PIO pio, uint sm, uint offset, float clkdiv) {
     pio_sm_config c = iow_program_get_default_config(offset);
 
     // Set up AD0 pins as input
     sm_config_set_in_pins(&c, AD0_PIN);
     // Autopush at 18 bits (10 addr + 8 data)
     sm_config_set_in_shift(&c, false, true, 18);
+    sm_config_set_clkdiv(&c, clkdiv);
 
     // Autopull 32 bits (condition variables from handle_ior)
     sm_config_set_out_shift(&c, true, true /* autopull */, 32);

diff --git a/sw/picogus.cpp b/sw/picogus.cpp
@@ -550,6 +550,7 @@ void err_blink(void) {
 constexpr uint32_t rp2_clock = 366000;
 constexpr float psram_clkdiv = (float)rp2_clock / 200000.0;
 constexpr float pwm_clkdiv = (float)rp2_clock / 22727.27;
+constexpr float iow_clkdiv = (float)rp2_clock / 183000.0;
 
 constexpr uint32_t iow_rxempty = 1u << (PIO_FSTAT_RXEMPTY_LSB + IOW_PIO_SM);
 __force_inline bool iow_has_data() {
@@ -778,7 +779,7 @@ int main()
     pio_sm_claim(pio0, IOR_PIO_SM);
     printf("ior sm: %u\n", IOR_PIO_SM);
 
-    iow_program_init(pio0, IOW_PIO_SM, iow_offset);
+    iow_program_init(pio0, IOW_PIO_SM, iow_offset, iow_clkdiv);
     ior_program_init(pio0, IOR_PIO_SM, ior_offset);
 
 #ifdef USE_IRQ