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pico-serprog
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add support for multiple chip selects 

now, GP5..8 are available as cs=0..3
GP5 is still the default one, which is defaulted to on power-up.

Signed-off-by: Riku Viitanen <riku.viitanen@protonmail.com>
This commit is contained in:
Riku Viitanen 2024-01-15 19:28:00 +02:00
parent 0d49d6fcbe
commit 6301fbf3ed
2 changed files with 70 additions and 32 deletions
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100
main.c
View File

@ -1,6 +1,6 @@
/**
* Copyright (C) 2021, Mate Kukri <km@mkukri.xyz>
* Copyright (C) 2023, Riku Viitanen <riku.viitanen@protonmail.com>
* Copyright (C) 2023, 2024, Riku Viitanen <riku.viitanen@protonmail.com>
* Based on "pico-serprog" by Thomas Roth <code@stacksmashing.net>
*
* Licensed under GPLv3
@ -23,29 +23,42 @@
#define SPI_IF spi0 // Which PL022 to use
#define SPI_BAUD 12000000 // Default baudrate (12 MHz)
#define SPI_CS 5
#define SPI_CS_0 5 // The default CS pin
#define SPI_MISO 4
#define SPI_MOSI 3
#define SPI_SCK 2
uint8_t spi_enabled = 0;
uint cs_pin = SPI_CS_0;
#define NUM_CS_AVAILABLE 4 // Number of usable chip selects
static const char progname[16] = "pico-serprog";
/* Map of supported serprog commands */
static const uint32_t cmdmap[8] = {
(1 << S_CMD_NOP) |
(1 << S_CMD_Q_IFACE) |
(1 << S_CMD_Q_CMDMAP) |
(1 << S_CMD_Q_PGMNAME) |
(1 << S_CMD_Q_SERBUF) |
(1 << S_CMD_Q_BUSTYPE) |
(1 << S_CMD_SYNCNOP) |
(1 << S_CMD_O_SPIOP) |
(1 << S_CMD_S_BUSTYPE) |
(1 << S_CMD_S_SPI_FREQ)|
(1 << S_CMD_S_PIN_STATE)
(1 << S_CMD_NOP) |
(1 << S_CMD_Q_IFACE) |
(1 << S_CMD_Q_CMDMAP) |
(1 << S_CMD_Q_PGMNAME) |
(1 << S_CMD_Q_SERBUF) |
(1 << S_CMD_Q_BUSTYPE) |
(1 << S_CMD_SYNCNOP) |
(1 << S_CMD_O_SPIOP) |
(1 << S_CMD_S_BUSTYPE) |
(1 << S_CMD_S_SPI_FREQ) |
(1 << S_CMD_S_PIN_STATE) |
(1 << S_CMD_S_SPI_CS)
};
static void enable_cs(uint pin)
{
gpio_init(pin);
gpio_put(pin, 1);
gpio_set_dir(pin, GPIO_OUT);
gpio_set_drive_strength(pin, GPIO_DRIVE_STRENGTH_12MA);
}
static void enable_spi(uint baud)
{
#ifdef PICO_DEFAULT_LED_PIN
@ -54,10 +67,7 @@ static void enable_spi(uint baud)
gpio_set_dir(PICO_DEFAULT_LED_PIN, GPIO_OUT);
#endif
// Setup chip select GPIO
gpio_init(SPI_CS);
gpio_put(SPI_CS, 1);
gpio_set_dir(SPI_CS, GPIO_OUT);
enable_cs(cs_pin);
// Setup PL022
spi_init(SPI_IF, baud);
@ -68,25 +78,39 @@ static void enable_spi(uint baud)
gpio_set_drive_strength(SPI_MISO, GPIO_DRIVE_STRENGTH_12MA);
gpio_set_drive_strength(SPI_MOSI, GPIO_DRIVE_STRENGTH_12MA);
gpio_set_drive_strength(SPI_SCK, GPIO_DRIVE_STRENGTH_12MA);
gpio_set_drive_strength(SPI_CS, GPIO_DRIVE_STRENGTH_12MA);
spi_enabled = 1;
}
static void disable_pin(uint pin)
{
gpio_init(pin); // Set pin to SIO input
gpio_set_pulls(pin, 0, 0); // Disable all pulls
}
static void disable_spi()
{
// Set all pins to SIO inputs
gpio_init(SPI_CS);
gpio_init(SPI_MISO);
gpio_init(SPI_MOSI);
gpio_init(SPI_SCK);
// Disable all pulls
gpio_set_pulls(SPI_CS, 0, 0);
gpio_set_pulls(SPI_MISO, 0, 0);
gpio_set_pulls(SPI_MOSI, 0, 0);
gpio_set_pulls(SPI_SCK, 0, 0);
disable_pin(cs_pin);
disable_pin(SPI_MISO);
disable_pin(SPI_MOSI);
disable_pin(SPI_SCK);
// Disable SPI peripheral
spi_deinit(SPI_IF);
spi_enabled = 0;
}
static void set_cs_pin(uint8_t cs)
{
cs += SPI_CS_0;
if (spi_enabled) {
if (cs_pin != cs) {
disable_pin(cs_pin);
enable_cs(cs);
}
}
cs_pin = cs;
}
static inline void cs_select(uint cs_pin)
@ -198,7 +222,7 @@ static void process_command(uint8_t cmd, uint *baud) {
uint32_t rlen = 0;
readbytes_blocking(&rlen, 3);
cs_select(SPI_CS);
cs_select(cs_pin);
while (wlen) {
uint32_t cur = MIN(wlen, sizeof buf);
@ -216,7 +240,7 @@ static void process_command(uint8_t cmd, uint *baud) {
rlen -= cur;
}
cs_deselect(SPI_CS);
cs_deselect(cs_pin);
}
break;
case S_CMD_S_SPI_FREQ:
@ -242,6 +266,15 @@ static void process_command(uint8_t cmd, uint *baud) {
disable_spi();
sendbyte_blocking(S_ACK);
break;
case S_CMD_S_SPI_CS:
uint8_t cs_index = readbyte_blocking();
if (cs_index < NUM_CS_AVAILABLE) {
set_cs_pin(cs_index);
sendbyte_blocking(S_ACK);
} else {
sendbyte_blocking(S_NAK);
}
break;
default:
sendbyte_blocking(S_NAK);
break;
@ -280,7 +313,10 @@ int main()
bi_decl(bi_1pin_with_name(SPI_MISO, "MISO"));
bi_decl(bi_1pin_with_name(SPI_MOSI, "MOSI"));
bi_decl(bi_1pin_with_name(SPI_SCK, "SCK"));
bi_decl(bi_1pin_with_name(SPI_CS, "CS"));
bi_decl(bi_1pin_with_name(SPI_CS_0, "CS_0 (default)"));
bi_decl(bi_1pin_with_name(SPI_CS_0+1, "CS_1"));
bi_decl(bi_1pin_with_name(SPI_CS_0+2, "CS_2"));
bi_decl(bi_1pin_with_name(SPI_CS_0+3, "CS_3"));
// Setup USB
tusb_init();

2
serprog.h
View File

@ -28,4 +28,6 @@
#define S_CMD_S_SPI_FREQ 0x14 /* Set SPI clock frequency */
#define S_CMD_S_PIN_STATE 0x15 /* Enable/disable output drivers */
#define S_CMD_S_SPI_CS 0x16 /* Select Chip Select to use */
#endif